Merge pull request #726: fix(terminal): don't double a desktop dead key, and bracket Ctrl+V after replay

docs/architecture-invariants.md

@@ -817,7 +817,7 @@ Feedback is silent on success except ONCE per page load (a feature that works by
 
 ### Terminal paste (Ctrl+V)
 
-**The Ctrl+V paste trap consumes exactly ONE paste event.** `_handleImagePaste()` (image-input.js) appends a hidden `contenteditable` div, focuses it, and reads the clipboard out of the paste event that lands there. An image becomes an upload whose saved path is typed into the session; text goes through `terminal.paste()`, so the bracketed-paste markers survive. Two independent routes deliver that event for one keypress, and a browser may fire both:
+**The Ctrl+V paste trap consumes exactly ONE paste event.** `_handleImagePaste()` (image-input.js) appends a hidden `contenteditable` div, focuses it, and reads the clipboard out of the paste event that lands there. An image becomes an upload whose saved path is typed into the session; plain text is a Codeman-built bracketed paste (`\x1b[200~` … `\x1b[201~`, nested markers stripped, newlines as `\r`) handed to that pane's terminal via `terminal.input(framed)`. `terminal.paste()` only emits those markers while xterm's DECSET 2004 mirror is on, and a terminal replay clears that mirror (#716), so Ctrl+V builds the frame itself. `input()` fires onData as user input, which scrolls to the bottom and clears the selection. The main pane's onData bracketed-paste branch and a tile's `_onTerminalData` deliver the frame, which is where the local-echo flush and the delayed write live (#219). A frame wrapped in CSI 200~/201~ does not match the query-reply or mouse-report filters. The terminal is refocused; the paste is not written into the xterm buffer. Two independent routes deliver that event for one keypress, and a browser may fire both:
 
 1. **`document.execCommand('paste')`**, which the function calls itself. ⚠️ Its return value proves nothing about whether it fired. Firefox dispatches a trusted `paste` event carrying the real clipboard and still returns `false`, because the trap cancels the event and the command therefore never completes. Chromium refuses the command outright and dispatches nothing.
 2. **The keydown's own default action.** The `Ctrl+V` branch in `attachCustomKeyEventHandler` returns `false`, which stops xterm from evaluating the key into `^V` but does not cancel the DOM event, for the same reason rule 1 of smart copy above spells out. `trap.focus()` has already run by then, so the browser sends its own paste to the trap as well.