tools(relay): durable JSONL message log + pm wrapper + 120-char preview

- queue.ts: append every posted message to relay-log.jsonl (full body,
  survives the consume-once drain + restarts). gitignored.
- server.ts: bump the stdout preview from 60 to 120 chars.
- tools/relay/pm: absolute-path bash wrapper (read|pending|send) so relay
  ops work from any cwd without cd or hand-built JSON escaping.
- Fold in Dev-C's Phase 6 ARCHITECTURE.md slice as a coordination artifact.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tools/relay/server.ts

@@ -86,8 +86,8 @@ function handleToolCall(name: string, args: Record<string, string>) {
     const kind = args.kind as "status" | "question" | "directive" | "free";
     const msg = queue.post(args.from, args.to, kind, args.body);
     const ts = new Date(msg.ts).toTimeString().slice(0, 8);
-    const preview = args.body.slice(0, 60).replace(/\n/g, " ");
-    const ellipsis = args.body.length > 60 ? "..." : "";
+    const preview = args.body.slice(0, 120).replace(/\n/g, " ");
+    const ellipsis = args.body.length > 120 ? "..." : "";
     process.stdout.write(`[${ts}] ${args.from} → ${args.to}  [${kind}]  "${preview}${ellipsis}"\n`);
     return { content: [{ type: "text" as const, text: JSON.stringify({ id: msg.id }) }] };
   }