fix(tui): accept Alt+G as Ctrl+G fallback in VSCode/Cursor terminals

VSCode and Cursor bind Ctrl+G to "Find Next" at the editor level, so
the keystroke never reaches the embedded terminal — Ctrl+G to open
\$EDITOR was effectively dead inside those IDEs.

Alt+G is unbound in both editors and reaches the TUI cleanly as
`\x1bg` → `key.meta && ch === 'g'` after parse-keypress. Accept it
alongside the existing isAction(key, ch, 'g') check, and document the
fallback in README + the hotkeys panel.

ui-tui/src/app/useInputHandlers.ts

@@ -366,7 +366,10 @@ export function useInputHandlers(ctx: InputHandlerContext): InputHandlerResult {
       return voiceRecordToggle()
     }
 
-    if (isAction(key, ch, 'g')) {
+    // Alt+G is the escape hatch for terminals that swallow Ctrl+G — VSCode and
+    // Cursor bind it to "Find Next" by default, so the keystroke never reaches
+    // the embedded TUI. Alt+G arrives as `\x1bg` → meta+g across platforms.
+    if (isAction(key, ch, 'g') || (key.meta && ch.toLowerCase() === 'g')) {
       return cActions.openEditor()
     }
 

ui-tui/src/content/hotkeys.ts

@@ -18,7 +18,7 @@ const copyHotkeys: [string, string][] = isMac
 export const HOTKEYS: [string, string][] = [
   ...copyHotkeys,
   [action + '+D', 'exit'],
-  [action + '+G', 'open $EDITOR for prompt'],
+  [action + '+G / Alt+G', 'open $EDITOR for prompt (Alt+G in VSCode/Cursor)'],
   [action + '+L', 'new session (clear)'],
   [paste + '+V / /paste', 'paste text; /paste attaches clipboard image'],
   ['Tab', 'apply completion'],