Add API server with routes, services, and middleware

Express server with CRUD routes for agents, goals, issues, projects,
and activity log. Includes validation middleware, structured error
handling, request logging, and health check endpoint with tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/routes/agents.ts

@@ -0,0 +1,52 @@
+import { Router } from "express";
+import type { Db } from "@paperclip/db";
+import { createAgentSchema, updateAgentSchema } from "@paperclip/shared";
+import { validate } from "../middleware/validate.js";
+import { agentService } from "../services/agents.js";
+
+export function agentRoutes(db: Db) {
+  const router = Router();
+  const svc = agentService(db);
+
+  router.get("/", async (_req, res) => {
+    const result = await svc.list();
+    res.json(result);
+  });
+
+  router.get("/:id", async (req, res) => {
+    const id = req.params.id as string;
+    const agent = await svc.getById(id);
+    if (!agent) {
+      res.status(404).json({ error: "Agent not found" });
+      return;
+    }
+    res.json(agent);
+  });
+
+  router.post("/", validate(createAgentSchema), async (req, res) => {
+    const agent = await svc.create(req.body);
+    res.status(201).json(agent);
+  });
+
+  router.patch("/:id", validate(updateAgentSchema), async (req, res) => {
+    const id = req.params.id as string;
+    const agent = await svc.update(id, req.body);
+    if (!agent) {
+      res.status(404).json({ error: "Agent not found" });
+      return;
+    }
+    res.json(agent);
+  });
+
+  router.delete("/:id", async (req, res) => {
+    const id = req.params.id as string;
+    const agent = await svc.remove(id);
+    if (!agent) {
+      res.status(404).json({ error: "Agent not found" });
+      return;
+    }
+    res.json(agent);
+  });
+
+  return router;
+}