fix(terminal): one touch contact is one paging gesture; bound slow ticks and wobble

Review of #527 (Ark0N, 2026-10-11):

1. A slow touch drag paged a full screen per line. touchmove calls the
   fallback once per whole cell, so a slow drag's calls were further apart
   than the 150 ms gesture gap and each pre-paid a page (12 lines at 170 ms
   sent 12 PageUps). The touch paths now tag every call, touchmove and
   momentum frames alike, with a per-contact touchId (incremented on
   touchstart), and pageKeysForGesture never splits a contact by time; a
   new contact is a new gesture.
2. A pre-paid debt now survives up to PAGE_KEY_DEBT_MS (1 s) of quiet when
   the next event goes the same way, so slow small wheel ticks (40 px every
   250 ms, a Firefox 1-line notch) pay it back instead of each pre-paying.
   A reversal inside the gap (or inside one contact) drops the debt and
   accumulates without pre-paying, so a +/-3 px wobble no longer pages
   back and forth. A reversal after the gap still pages at once. Main pane
   and tiles share the helper, so both get it.
3. A wheel consumed by the dialog check now logs page-keys-dialog-open.
4. The Dashboard wiki names newer Codex beside OpenCode; the invariants
   paragraph describes the new gesture boundaries.

Tests: unit regressions through the real _maybePageCliTranscript, helper
cases, tile/main parity for ticks and wobble, and a Chromium test that
drives the real initTerminal touch listeners (12 PageUps before, 1 after).

config/test-suites.ts

@@ -35,6 +35,7 @@ export const BROWSER_TEST_GLOBS = [
   'test/codex-predictive-echo.test.ts', // also needs a real codex binary
   'test/split-pane-terminal.browser.test.ts',
   'test/terminal-tile-scroll.browser.test.ts',
+  'test/terminal-touch-paging.browser.test.ts',
   'test/shift-enter-keypress.browser.test.ts',
   'test/key-tester.browser.test.ts',
   'test/webhook-settings.browser.test.ts',