Pipe winston logs to dashboard + add Matrix sniff debug route

The dashboard's /api/logs buffer only ever saw lines explicitly pushed
via broadcaster.push, so winston output (including the Matrix
token-extractor's timeout diagnostics) was invisible from the deployed
container. Attach a winston transport that forwards every entry into the
LogBroadcaster before the rest of bootstrap runs, so the matrix sniff's
`finalUrl=... hosts=[...]` line shows up in /api/logs.

Also serve data/matrix-debug.png (the screenshot the extractor drops on
timeout) at /api/debug/matrix-debug.png so we can see what
chat.reddit.com looked like in the headed browser without shell access
to the Dokploy host.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/web/routes/debug.ts

@@ -1,9 +1,26 @@
 import { Router } from 'express';
+import path from 'path';
+import fs from 'fs';
 import type { WebContext } from '../context.js';
 
 export function createDebugRouter(ctx: WebContext): Router {
   const router = Router();
 
+  // Serves the screenshot dropped by the matrix token-extractor when the
+  // sniff times out (data/matrix-debug.png). Lets us see what chat.reddit.com
+  // looked like in the headed browser without needing host shell access.
+  router.get('/debug/matrix-debug.png', (_req, res) => {
+    const p = path.resolve(process.cwd(), 'data/matrix-debug.png');
+    if (!fs.existsSync(p)) {
+      res.status(404).json({ error: 'No matrix-debug.png yet — sniff has not failed since last clean start.' });
+      return;
+    }
+    const stat = fs.statSync(p);
+    res.set('Cache-Control', 'no-cache, no-store, must-revalidate');
+    res.set('X-Captured-At', stat.mtime.toISOString());
+    res.sendFile(p);
+  });
+
   router.post('/debug/inspect-dom', async (req, res) => {
     if (!ctx.services.chat) {
       res.status(500).json({ error: 'Chat service not initialized' });