add a transmission sidecar and ui

officer-transmission is a new pm2 peer that owns the transmission rpc
connection and exposes a curated /_officer/* contract instead of proxying
raw rpc. it absorbs the three quirks callers otherwise have to know about:
the 409 x-transmission-session-id handshake, failures returned as
{"result": "..."} inside http 200, and basic auth where an empty username
must send no header at all.

/transmission is the ui, on the workspace/panel framework: a filter nav and
three sections (torrents, stats, settings). the torrent list is virtualised
with 30 available columns, multi-select, and a right-click menu; the detail
pane covers general, files as a real tree, peers and trackers. filters and
the open torrent live in the url, so a filtered view is a link.

phase 1 goal was parity with _references/transmission-web. follow-up work is
recorded in TODO.md.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/apps/officer-web/state/usePageTitle.ts

@@ -18,6 +18,7 @@ const RULES: TitleRule[] = [
   { match: (p) => p.startsWith('/music'), title: 'Music' },
   { match: (p) => p.startsWith('/soulseek'), title: 'Soulseek' },
   { match: (p) => p.startsWith('/headscale'), title: 'Headscale' },
+  { match: (p) => p.startsWith('/transmission'), title: 'Transmission' },
   { match: (p) => p.startsWith('/system-monitor'), title: 'System Monitor' },
   { match: (p) => p.startsWith('/code-editor'), title: 'Code Editor' },
   { match: (p) => p.startsWith('/task-logs'), title: 'Task Logs' },