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/App.tsx

@@ -44,6 +44,8 @@ export function App() {
             <Route path="/soulseek" element={<Dashboard.SoulseekScreen />} />
             <Route path="/headscale" element={<Dashboard.HeadscaleScreen />} />
             <Route path="/headscale/:section" element={<Dashboard.HeadscaleScreen />} />
+            <Route path="/transmission" element={<Dashboard.TransmissionScreen />} />
+            <Route path="/transmission/:section" element={<Dashboard.TransmissionScreen />} />
             <Route path="/system-monitor" element={<Dashboard.SystemMonitorScreen />} />
             <Route path="/activity" element={<Dashboard.ActivityScreen />} />
 

src/apps/officer-web/Screens/Dashboard/Layout/Dock.tsx

@@ -135,6 +135,7 @@ import {
   Activity,
   Radio,
   Network,
+  ArrowDownUp,
 } from 'lucide-react';
 
 export const ALL_DOCK_ITEMS: DockItem[] = [
@@ -145,6 +146,7 @@ export const ALL_DOCK_ITEMS: DockItem[] = [
   { label: 'Music', to: '/music', icon: Music, color: '#22c55e' },
   { label: 'Soulseek', to: '/soulseek', image: '/slskd.png', color: '#ffffff' },
   { label: 'Headscale', to: '/headscale', icon: Network, color: '#818cf8' },
+  { label: 'Transmission', to: '/transmission', icon: ArrowDownUp, color: '#e11d48' },
   { label: 'Editor', to: '/code-editor', icon: Code, color: '#a78bfa' },
   { label: 'Plans', to: '/plans', icon: FileText, color: '#f472b6' },
   { label: 'Jobs', to: '/jobs', icon: Workflow, color: '#14b8a6' },

src/apps/officer-web/Screens/Dashboard/Transmission/TransmissionScreen.tsx

@@ -0,0 +1,63 @@
+import { useEffect, useMemo } from 'react';
+import { Navigate, useParams } from 'react-router';
+import type { LayoutNode } from 'officerdev';
+import {
+  WorkspaceView,
+  DEFAULT_TRANSMISSION_SECTION,
+  transmissionSectionPath,
+  isTransmissionSection,
+} from 'officerdev';
+import { useDashboardState } from 'state/useDashboardState';
+import { defaultLayout } from './defaultLayout';
+
+// /transmission uses the Workspace/Panel system (like /headscale): a filter nav on the left and the section
+// view on the right. Both talk to the officer-transmission sidecar through the /api/transmission auth proxy,
+// which holds no Transmission credentials of its own — the RPC URL and any Basic auth live in the sidecar.
+//
+// The open section is :section in the URL and the torrent filters are query params, so both panels read the
+// URL with useParams/useSearchParams instead of passing state between themselves over a channel. This screen
+// backs both /transmission and /transmission/:section and is the single place that decides what an absent or
+// bogus section means.
+
+const ALLOWED_APP_TYPES = new Set<string | null>(['transmission-nav', 'transmission-view', null]);
+
+function normalizeLayout(node: LayoutNode): LayoutNode {
+  if (node.type === 'panel') {
+    return ALLOWED_APP_TYPES.has(node.appType) ? node : { ...node, appType: 'transmission-view' };
+  }
+  const children = node.children.map((c) => {
+    const fixed = normalizeLayout(c.node);
+    return fixed === c.node ? c : { ...c, node: fixed };
+  });
+  const changed = children.some((c, i) => c !== node.children[i]);
+  return changed ? { ...node, children } : node;
+}
+
+export const TransmissionScreen = () => {
+  const { section } = useParams();
+  const rawWorkspace = useDashboardState<LayoutNode>('screens/transmission', defaultLayout);
+
+  const workspace = useMemo(() => {
+    const fixed = normalizeLayout(rawWorkspace.value);
+    if (fixed === rawWorkspace.value) return rawWorkspace;
+    return { ...rawWorkspace, value: fixed };
+  }, [rawWorkspace]);
+
+  useEffect(() => {
+    if (rawWorkspace.isLoaded && workspace.value !== rawWorkspace.value) {
+      rawWorkspace.setValue(workspace.value);
+    }
+  }, [rawWorkspace.isLoaded, workspace.value, rawWorkspace.value]);
+
+  // Bare /transmission, or a section that doesn't exist, resolves to a canonical URL rather than rendering a
+  // default while the address bar says something else — the nav highlight is derived from the URL.
+  if (!isTransmissionSection(section)) {
+    return <Navigate to={transmissionSectionPath(DEFAULT_TRANSMISSION_SECTION)} replace />;
+  }
+
+  return (
+    <div className="h-full w-full pt-2">
+      <WorkspaceView workspace={workspace} locked />
+    </div>
+  );
+};

src/apps/officer-web/Screens/Dashboard/Transmission/defaultLayout.ts

@@ -0,0 +1,11 @@
+import type { LayoutNode } from 'officerdev';
+
+export const defaultLayout: LayoutNode = {
+  type: 'group',
+  id: 'transmission-root',
+  direction: 'horizontal',
+  children: [
+    { node: { type: 'panel', id: 'transmission-nav', appType: 'transmission-nav' }, size: 22 },
+    { node: { type: 'panel', id: 'transmission-view', appType: 'transmission-view' }, size: 78 },
+  ],
+};

src/apps/officer-web/Screens/Dashboard/Transmission/index.tsx

@@ -0,0 +1 @@
+export * from './TransmissionScreen';

src/apps/officer-web/Screens/Dashboard/index.tsx

@@ -13,6 +13,7 @@ export * from './Files';
 export * from './Music';
 export * from './Soulseek';
 export * from './Headscale';
+export * from './Transmission';
 export * from './SystemMonitor';
 export * from './Activity';
 export * from './CodeEditor';

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' },