v0.1.1

Validation release for the self-update detection and agent-driven upgrade flow.
No new features — minor i18n wording adjustments to provide a known surface
for upgrade-time merge handling.

Changed

• onboarding.welcome.subtitle: rephrased the welcome subtitle on the
  onboarding screen (src/renderer/i18n/{ja,en}.ts).
• ambientSidebar.placeholder: rephrased the empty-state hint shown in the
  ambient session sidebar (src/renderer/i18n/{ja,en}.ts).
• version.loadFailed: rephrased the error message displayed when version
  information cannot be loaded (src/renderer/i18n/{ja,en}.ts).