feat(api): implement authenticated habit tracking and combined calendars

src/api.ts

@@ -1,3 +1,5 @@
+import { createHabitRoutes } from "./habits/routes";
+import { ApiError } from "./habits/service";
 import { Hono } from "hono";
 import { sql } from "drizzle-orm";
 import { createAuth, type AppDatabase, type AuthEnv } from "./auth";
@@ -13,9 +15,11 @@ export function createApi(db: AppDatabase, config: AuthConfig, request?: FetchDi
   });
   app.route("/api/auth", auth.routes);
   app.get("/api/me", auth.requireAuth, c => c.json(c.get("user")));
+  app.route("/api", createHabitRoutes(db, auth, now ?? Date.now));
   app.notFound(c => c.json({ error: "Not found" }, 404));
   app.onError((_error, c) => {
     c.header("Cache-Control", "no-store");
+    if (_error instanceof ApiError) return c.json({ error: _error.message }, _error.status);
     return c.json({ error: "Internal server error" }, 500);
   });
   return app;