Rename the service to BugTrail ...

Bug + trail: the recorded trail of actions leading to the bug.
User-facing rename in the web panel shell, extension manifest/popup/
options, API title, i18n locales and README; Firefox id is now
bugtrail@gnexus.space. Internal @ltt/* package scopes unchanged.

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

Extension: popup UI, panel URL, icon fix, GIF tracks and track replay ...

- Popup replaces the auto-start picker: mode choice (element note /
  record steps), latest report card with open / replay / delete, web
  panel link; share links open at panelUrl (default :5173)
- Register the Phosphor font via the FontFace API — constructable
  stylesheets ignore @font-face, which left overlay icons empty
- Recorder tracks upload as one animated GIF (gifenc) instead of per-
  step screenshots; frames follow event pacing, UI hidden on capture
- Replay a recorded track from the popup: background opens the start
  page, re-executes click/input/url_change steps with original pacing
  and flashes the result in the overlay

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

Extension popup: mode choice, latest report, panel link; auto-copied share links ...

- Toolbar click now opens a popup instead of jumping straight into the
  picker: two mode buttons (element note / record steps with live step
  count), the latest report of the default project with open and
  two-step delete, and an "Open web panel" shortcut to the project page.
- New background messages (start_picker, toggle_recorder, latest_report,
  delete_report, open_panel) resolve the active tab themselves; the
  action.onClicked path stays for keyboard-driven flows.
- Settings gain panelUrl (falls back to serverUrl); options page gets a
  "Web panel URL" input.
- After a note is submitted its share link is copied to the clipboard
  automatically (with an execCommand fallback) and a brief toast
  confirms it; e2e asserts the clipboard content.
- Build: new popup entry (own CSS chunk), manifest default_popup.

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