fix(terminal): address review: Key tester isolates shortcuts, Codex stays on line feed

- app.js: the shortcut dispatcher returns early for events aimed at a data-raw-keys
  field, so Ctrl+W / Ctrl+L / Escape / Alt+1 / Ctrl+K pressed in the Key tester no
  longer kill the session, clear the terminal or close Settings
- stock.ts: drop Codex's esc-enter (a line feed works); no stock CLI declares a chord.
  The esc-enter path is tested through a clis.json override
- tests: unused port (3194), Ctrl+Enter asserts no keypress, shortcut-isolation test
  (verified to fail without the guard)
- docs/comments point at capabilities.newline; set-input class, trailing whitespace

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/web/routes/session-routes.ts

@@ -2093,8 +2093,9 @@ export function registerSessionRoutes(
 
   // ========== Send Named Key (tmux send-keys -H) ==========
   // Sends raw hex bytes to tmux pane for keys like Shift+Enter / Ctrl+Enter.
-  // Uses send-keys -H (hex) to inject 0x0a (line feed) which Claude Code's
-  // Ink input recognizes as "insert newline" vs 0x0d (carriage return = submit).
+  // Uses send-keys -H (hex) to inject a newline chord: 0x0a (line feed) by default, or the CLI's
+  // own `capabilities.newline`. Claude Code's Ink input recognizes 0x0a as "insert newline" vs
+  // 0x0d (carriage return = submit).
 
   app.post('/api/sessions/:id/send-key', async (req) => {
     const { id } = req.params as { id: string };