feat: shortcut recorder, configurable terminal toolbar, offline changelog

- Global shortcut setting: press-to-record input (Esc cancels, Backspace
  clears); requires a modifier or F-key so plain typing can't be hijacked
- Terminal toolbar: three settings-gated buttons — session-log record
  (default off), open logs dir (default off), open working directory
  (default on, new; local sessions only, cwd tracked via cd/OSC 7)
- Input suggestions + command history now default off, with a one-time
  migration that resets persisted true values for existing installs
- Settings dialog: fix broken scrolling — antd v6 renamed the Tabs scroll
  container to .ant-tabs-body-holder; theme gallery drops its nested
  scroll (single outer scrollbar)
- Offline changelog: CHANGELOG.md at repo root bundled via ?raw; About tab
  reads it first, network sources stay as fallback; scripts/sync-changelog.cjs
  merges RELEASE_NOTES.md per release (release.cjs fails without an entry)
- commands.ts history prefs default aligned with new off-by-default

src/shared/api.ts

@@ -80,6 +80,8 @@ export interface AppApi {
   logStop(sessionId: string): Promise<void>
   listSessionLogs(): Promise<SessionLogMeta[]>
   openLogsDir(): void
+  /** open a local directory in the OS file manager; false if not a directory */
+  openDirectory(dir: string): Promise<boolean>
 
   // ---- ssh connections ----
   listConnections(): Promise<SshConnection[]>