Ukrainian localization; link-preview meta tags on share pages ...

- uk.json: full Ukrainian translation, uk added to SUPPORTED_LOCALES with
  the shared slavic plural rules and a language option in settings
- /p/<token> and /r/<token> are now served by the API: it injects
  og:title/description/url/image/video + twitter:card into the panel's
  index.html so Telegram and Jira previews show the project or report
  (title, description, creation date, screenshot/video). Caddy proxies
  those paths to the server; the public origin comes from PUBLIC_BASE_URL
  or the request host. Verified end-to-end through the prod stack.

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

v0.1.0-beta: production transfer guide and parameterized prod stack ...

- docker-compose.prod.yml reads POSTGRES_PASSWORD, HTTP(S)_PORT and
  SITE_ADDRESS from .env; caddy persists its config in a volume
- Caddyfile takes the site address from the environment — a DNS name
  turns on automatic HTTPS
- README: full first-transfer, domain/HTTPS, update and backup guide

Smoke-tested locally: fresh postgres migrates on boot, panel + /api
serve from one origin, SPA fallback works.

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

Extension: picker, note composer, recorder + infra (Makefile, prod compose, README) ...

- MV3 extension for Chrome and Firefox: single codebase, per-entry IIFE
  builds (background / content / options), manifests generated per target
- Background service worker owns all networking (Bearer token from
  storage.local), captureVisibleTab (windowId!), recorder event buffer
  with offset_ms and auto-screenshots on clicks
- Content overlay in a closed shadow root (constructable stylesheets,
  kit CSS fetched from assets/style.css with /assets URL rewrite);
  PickerLayer, NoteComposer (autofocus, Ctrl+Enter submit),
  RecorderBar (step counter, note, stop)
- Options page: server URL, login, default project
- Recorder steps link screenshots by uploaded file id (server accepts
  attachment id or file id); environment/element JSONB serialized with
  mode="json" (datetime captured_at broke inserts)
- e2e harness: headless Chromium + extension, note + recording flows
- Makefile, docker-compose.prod.yml (caddy :8081 + static panel),
  deploy/Caddyfile, README (ru) with extension install and /assets notes

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