Report page: swap header buttons, fix back navigation on share links ...

- the copy-link button now comes before "Start replay" in the header
- "Back to project" no longer depends on in-app history: on a cold
  share-link visit (note or recording opened by URL) it falls back to
  the report's project page — the detail GET now returns
  project_share_token; without a project reference it goes to the
  projects list

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

Record silent WebM screen video instead of GIF during recordings ...

The recorder now captures continuous screencast frames via the CDP
screencast API and encodes them into a silent WebM (VP8, ~15 fps, capped
at 800px wide) uploaded as recording.webm. WebCodecs VideoEncoder is not
exposed to service workers, so encoding runs in an offscreen document
(chrome.offscreen) fed by base64 frame batches over a runtime port; the
result is verified with a local <video> playback probe and falls back to
the cursor-following GIF when encoding or verification fails (Firefox,
old Chrome, broken output).

Root cause of the earlier corrupt output: webm-muxer silently produces a
broken file when the first chunk's timestamp is non-zero — media
timestamps now start at the first frame and the muxer uses
firstTimestampBehavior: "offset".

The e2e now validates the uploaded recording with ffprobe (vp8 codec,
positive duration) and still covers the GIF fallback path, console-step
dump, navigation survival and replay.

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

Record the mouse path and play it back with a virtual cursor ...

- Recording: content script samples mousemove at ~25 Hz (2 px / 40 ms
  thresholds), batches it to the background every second and before
  submit; stored as reports.mouse_track (viewport + points, capped and
  decimated server-side) via a new alembic migration
- Replay: a virtual cursor (overlay arrow) walks the recorded path,
  scaled to the current viewport, dispatching synthetic mousemoves so
  JS hover handlers stay live; clicks snap the cursor to the target
- Replay errors: page-load timeout aborts with a clear message, a
  closed tab aborts, per-step failures (missing elements) are
  collected, reported in the flash and in the replay result
- Panel: "Start replay" button on recording reports talks to the
  extension through a new tiny relay content script (window messages,
  no extension-id config), with presence check and toasts for
  missing extension / no response / partial replay (en + ru)

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>

Web panel: Vue 3 + gnexus-ui-kit, auth, projects, reports, i18n ...

- Monorepo packages: @ltt/shared (types+client), @ltt/ui (AnnotationEditor,
  ScreenshotViewer, ElementContext, EnvironmentInfo), @ltt/web (panel)
- Kit assets served at /assets in dev and build (absolute font URL workaround)
- Pages: login/register, projects, public project+report pages (token=auth),
  settings with en/ru switcher
- Annotation editor: pen/arrow/rect/text, Tokyo Night palette, undo,
  fraction coordinates, vector shapes persisted via attachment PATCH

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

Server: FastAPI backend with auth, projects, reports, uploads ...

- FastAPI + SQLAlchemy async + Alembic, PostgreSQL in docker-compose
- Auth: argon2id, cookie sessions (web) + bearer tokens (extension)
- Unguessable share tokens (128-bit) on projects and reports
- Content-addressed file storage with mime sniffing, token-scoped download
- Reports with nested steps; server-side password masking

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