v0.4.7 — Connection status banner + privacy test coverage

• Reconnecting banner: when the connection to your opencode server drops,
  an amber "Reconnecting… (attempt N)" banner appears in the session view.
  A green "Connected ✓" flash confirms when the connection recovers.

• Push notifications: permission requests and agent questions now fire an
  OS push notification when the app is backgrounded — title "Agent needs
  approval" with dedup so reconnects don't re-fire the same notification.

• Privacy: URL credential scrubbing (basic-auth, token, api_key, password)
  now has 13 automated unit tests. Any regression will fail CI before shipping.

• Internal: pure scrub module extracted for testability; goal.md and TDD
  docs updated to reflect current shipped state.