feat(tiles): move tiles by hand, and detach a tile into its own window

Gesture control now moves tiles: with the tile grid open, pinch anywhere
on a tile and carry it onto another tile (they swap) or an empty cell (it
moves there); a session tab carried onto the grid joins it there. The
overlay asks tile-grid.js what is under the hand (tileAtPoint,
tileDropTargetAt) and drops through the mouse drag's own paths
(dropSessionOnTile / dropSessionOnSlot, so _reorderTiles stays the one
move path).

Detach Tiles (App Settings > Appearance, per device, OFF by default,
desktop only):
- a tile's header let go outside the browser window opens the session as
  a pop-out (detachSession, which now takes an optional size and screen
  position), the tile's size, near the drop point, after a 120 ms settle;
- dropped on another Codeman window's tiles it moves there: that window
  docks it through the target's own drop and posts 'tile-adopted' on the
  window channel, and only the window it was dragged from lets go of its
  copy (a last tile goes to the welcome screen, never onto that session);
- a pop-out's title drags back onto any grid: the session is taken back,
  the pop-out is asked to close and is released (stops answering
  roll-calls; one a script cannot close says where the session went), and
  its stale 'detached' answers are ignored for 2 s;
- a tile's menu offers "Open in a new window", and a hand that lets a tile
  go outside the grid pops it out too.

With the setting off nothing changes. No server change.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -280,7 +280,7 @@ Codeman is a Claude Code session manager with web interface and autonomous Ralph
 
 **Split-pane sessions** (`showSplitButton`, header button, default OFF, desktop-only at 1180px (width alone, so a wide Android tablet clears it), per-device): a second live session ("Pane B") beside the active one, in a `TerminalTile` (terminal-tile.js; the picker, divider and auto-collapse stay in terminal-split.js) with its own xterm + WebSocket, resizable via a draggable divider. Pane B reconnects after a drop, sends input through the exactly-once queue over its own socket (`_registerInputSocket`), has clickable paths and image paste, and owns its geometry (no 40x10 floor, `zc` columns adopted, font changes call `tile.fit()`). ⚠️ Only typed input enters that persisted queue: xterm's query replies are dropped and focus/mouse reports go out ephemeral. ⚠️ App-level terminal actions find their pane through `_focusedPane()` (the terminal focused last), never `this.terminal`. Still plainer than the primary pane (no local-echo overlay, CJK IME textarea or touch handlers), though it wires the same keyCode-229 soft-keyboard controller (Android autocorrect, #441/#541), and NOT persisted across reloads. The tile grid (below) reuses `TerminalTile`, and the two are never open together. → [architecture-invariants#split-pane-sessions](docs/architecture-invariants.md#split-pane-sessions)
 
-**Tile grid** (`showTileGridButton`, header Tiles button + `Ctrl+Shift+G`, default ON on desktop and OFF on handhelds and touch-primary tablets (primary pointer coarse, `getDefaultSettings()`; a touchscreen laptop keeps ON), desktop-only at 1180px, per-device; tile-grid.js, design `docs/tile-grid-plan.md`): 1 to 6 live sessions side by side (the cap is ONE constant, `TILE_GRID_MAX` in constants.js, owner decision; the layout table still covers 7 to 9, unreachable), each a `TerminalTile` with a header (state dot, harness logo, name, model, menu, zoom, ×; no +, owner decision), laid out by count (`CodemanTileGrid`, constants.js) with draggable column/row dividers, zoom (tmux-style), an Attach overlay, and per-browser persistence (`codeman:tile-grid`, localStorage only: cells with `null` holes, `count`, focus, user zoom, divider fractions, never content; written on every change, kept by EVERY close, restored INSIDE `handleInit` in place of the single-view select, so the main terminal never loads on that page load). While the grid is open the main terminal is PARKED: `activeSessionId` is the focused tile's session, and every main-terminal path that would write, fetch, resize or reconnect stands aside through `_tilesOwnTerminal()` (the WebGL long-task observer included). ⚠️ Every capture a tile fetches (initial, reconnect refresh, `{t:'r'}`, history pull) goes through ONE `TileLoadQueue` (concurrency 1, a deadline covering the body), because each is a synchronous tmux call on the server. ⚠️ Only a USER-initiated pick of a non-tiled session (or `leaveTiles`, a followed link) leaves the grid; an `auto` selection never collapses it, and every app-driven fallback (close, delete, restore) picks a tile. A caller of `closeTileGrid({ reselect: false })` must null `activeSessionId` before any `_cleanupPreviousSession`, or the parked terminal's stale content is saved as a snapshot. ⚠️ The grid and the split are never open together. ⚠️ Tile chords go through `tileShortcutFor` and are swallowed in every xterm key handler BEFORE the Shift+Enter gate; the toggle follows `showTileGridButton` (owner decision: OFF makes the chord inert, it passes through like any unbound key). ⚠️ The Tiles button's click and Ctrl+Shift+G are ONE function, `toggleTileGrid` (owner decision): they open the grid AT ONCE on `tileGridOpenSet` (constants.js): the stored grid EXACTLY as the user left it (owner decision 11: `restoreTileGridCells`, never filled to the count nor trimmed to the window; a cell whose session is gone since is filled from the ranking, a hole the user made stays), else an open split's two, else the open sessions as `rankTileSessions` orders them (working first, keyed off `lastSubmitAt` ONLY, then needing input, then most recent; `_mobileOverviewState`'s states), the active one focused, filled to the remembered count (`codeman:tile-count`, default 6, at most `_tileGridLimit()`) by `tileGridSetForCount`, never a menu. ⚠️ `removeTile(..., { gone: true })` (a session deleted, popped out or refused) keeps the stored `count` so the next open refills that cell; a removal by hand lowers it. Right-click is the 2 / 4 / 6 count menu (`openTileCountMenu`, owner decision 10), which owns its Escape. The button has no native title: its hover card (`_installTileGridHint`, `#tileGridHint`) says it, is its `aria-describedby` (always present, hidden, kept current) and hides in the capture phase on any press, click or right-click, so the menu never opens beside it. ⚠️ The open, the count menu and the toggle's close animate opacity and transform only (the close leaves an inert cloned still copy until the single view's selection settles, at most 700 ms); nothing moves under `prefers-reduced-motion`. ⚠️ Opening builds one tile terminal per frame (`_connectTilesPaced`), so `openTileGrid` returns before the terminals exist: focus is handed over in `_connectTile` (`focusOnConnect`). ⚠️ A divider drag reflows locally per frame and sends ONE resize per affected tile at pointer-up. ⚠️ The grid is CELLS (owner: an empty cell can be any cell): `grid.cells` (id or `null`) is the one source of truth, `grid.ids` a derived getter, never written; the shape still comes from the tile count, a shape change goes through `fitTileCells`, and the stored `ids` carry the cells with `null` holes. ⚠️ A tile moves (its header dragged or its tab dropped onto another tile or an empty cell, `Ctrl+Shift+Arrows`) ONLY through `_reorderTiles`: never a remount, reconnect or reload, and since sizes belong to the cells only a tile whose cell size changed fits; off while a tile is zoomed. The header drag carries its own type, never text, and is not `draggedTabId`; the header focuses on click, never on press, so a cancelled drag changes nothing. The arrow chords skip text fields. ⚠️ Sessions Run from this tab join the open grid (`_joinTileGridFromRun`, called from `_ensureCreatedSessionVisible`); sessions created elsewhere never do. SuchLine truncated
+**Tile grid** (`showTileGridButton`, header Tiles button + `Ctrl+Shift+G`, default ON on desktop and OFF on handhelds and touch-primary tablets (primary pointer coarse, `getDefaultSettings()`; a touchscreen laptop keeps ON), desktop-only at 1180px, per-device; tile-grid.js, design `docs/tile-grid-plan.md`): 1 to 6 live sessions side by side (the cap is ONE constant, `TILE_GRID_MAX` in constants.js, owner decision; the layout table still covers 7 to 9, unreachable), each a `TerminalTile` with a header (state dot, harness logo, name, model, menu, zoom, ×; no +, owner decision), laid out by count (`CodemanTileGrid`, constants.js) with draggable column/row dividers, zoom (tmux-style), an Attach overlay, and per-browser persistence (`codeman:tile-grid`, localStorage only: cells with `null` holes, `count`, focus, user zoom, divider fractions, never content; written on every change, kept by EVERY close, restored INSIDE `handleInit` in place of the single-view select, so the main terminal never loads on that page load). While the grid is open the main terminal is PARKED: `activeSessionId` is the focused tile's session, and every main-terminal path that would write, fetch, resize or reconnect stands aside through `_tilesOwnTerminal()` (the WebGL long-task observer included). ⚠️ Every capture a tile fetches (initial, reconnect refresh, `{t:'r'}`, history pull) goes through ONE `TileLoadQueue` (concurrency 1, a deadline covering the body), because each is a synchronous tmux call on the server. ⚠️ Only a USER-initiated pick of a non-tiled session (or `leaveTiles`, a followed link) leaves the grid; an `auto` selection never collapses it, and every app-driven fallback (close, delete, restore) picks a tile. A caller of `closeTileGrid({ reselect: false })` must null `activeSessionId` before any `_cleanupPreviousSession`, or the parked terminal's stale content is saved as a snapshot. ⚠️ The grid and the split are never open together. ⚠️ Tile chords go through `tileShortcutFor` and are swallowed in every xterm key handler BEFORE the Shift+Enter gate; the toggle follows `showTileGridButton` (owner decision: OFF makes the chord inert, it passes through like any unbound key). ⚠️ The Tiles button's click and Ctrl+Shift+G are ONE function, `toggleTileGrid` (owner decision): they open the grid AT ONCE on `tileGridOpenSet` (constants.js): the stored grid EXACTLY as the user left it (owner decision 11: `restoreTileGridCells`, never filled to the count nor trimmed to the window; a cell whose session is gone since is filled from the ranking, a hole the user made stays), else an open split's two, else the open sessions as `rankTileSessions` orders them (working first, keyed off `lastSubmitAt` ONLY, then needing input, then most recent; `_mobileOverviewState`'s states), the active one focused, filled to the remembered count (`codeman:tile-count`, default 6, at most `_tileGridLimit()`) by `tileGridSetForCount`, never a menu. ⚠️ `removeTile(..., { gone: true })` (a session deleted, popped out or refused) keeps the stored `count` so the next open refills that cell; a removal by hand lowers it. Right-click is the 2 / 4 / 6 count menu (`openTileCountMenu`, owner decision 10), which owns its Escape. The button has no native title: its hover card (`_installTileGridHint`, `#tileGridHint`) says it, is its `aria-describedby` (always present, hidden, kept current) and hides in the capture phase on any press, click or right-click, so the menu never opens beside it. ⚠️ The open, the count menu and the toggle's close animate opacity and transform only (the close leaves an inert cloned still copy until the single view's selection settles, at most 700 ms); nothing moves under `prefers-reduced-motion`. ⚠️ Opening builds one tile terminal per frame (`_connectTilesPaced`), so `openTileGrid` returns before the terminals exist: focus is handed over in `_connectTile` (`focusOnConnect`). ⚠️ A divider drag reflows locally per frame and sends ONE resize per affected tile at pointer-up. ⚠️ The grid is CELLS (owner: an empty cell can be any cell): `grid.cells` (id or `null`) is the one source of truth, `grid.ids` a derived getter, never written; the shape still comes from the tile count, a shape change goes through `fitTileCells`, and the stored `ids` carry the cells with `null` holes. ⚠️ A tile moves (its header dragged or its tab dropped onto another tile or an empty cell, `Ctrl+Shift+Arrows`) ONLY through `_reorderTiles`: never a remount, reconnect or reload, and since sizes belong to the cells only a tile whose cell size changed fits; off while a tile is zoomed. The header drag carries its own type, never text, and is not `draggedTabId`; the header focuses on click, never on press, so a cancelled drag changes nothing. The arrow chords skip text fields. ⚠️ Sessions Run from this tab join the open grid (`_joinTileGridFromRun`, called from `_ensureCreatedSessionVisible`); sessions created elsewhere never do. SuchLine truncated
 
 **Terminal touch gestures: link taps and text selection**: on touch devices xterm's linkifier and SelectionService never see the gesture, so both are driven explicitly (terminal-ui.js). ⚠️ A tap activates the link under it through the SAME provider as the hover linkifier (`_terminalLinkAtPoint`), synchronously inside `touchend` (keeps the user gesture `window.open` needs) and BEFORE any mouse report; the caret's logical line (`_tapIsOnCaretLine`) and TUI-owned rows (`_isActionableMobileTerminalTap`) keep their meaning. ⚠️ Gate on the caret line, never on tap intent (a shell calls every tap `'input'`). ⚠️ Long-press selects via xterm's public `select()`; keep the three guards: suppress the compat mouse pair after `touchend`, the bounded focus guard + `contextmenu` suppression for the platform long-press, and no closing `terminal.focus()` on phones. Tests: `test/terminal-touch-tap.test.ts`. → [architecture-invariants#terminal-touch-gestures-link-taps-and-text-selection](docs/architecture-invariants.md#terminal-touch-gestures-link-taps-and-text-selection)