Add User Model Service and Temporal Recall for MeMind V0.1.

Introduce UMS ingest/snapshot pipeline, Context Planner with multi-source recall, runtime context injection, canonical user mapping, and session snapshot loading on auth/me.

Co-authored-by: Cursor <cursoragent@cursor.com>

user-model-service/migrate.mjs

@@ -0,0 +1,21 @@
+#!/usr/bin/env node
+import { createUmsPool, isUmsDatabaseConfigured, runUmsSchema } from './db.mjs';
+
+async function main() {
+  if (!isUmsDatabaseConfigured()) {
+    console.error('UMS 未配置。请设置 UMS_DATABASE_URL 或 UMS_MYSQL_*');
+    process.exit(1);
+  }
+  const pool = createUmsPool();
+  try {
+    await runUmsSchema(pool);
+    console.log('memind_user_model schema v0 migrated successfully.');
+  } finally {
+    await pool.end();
+  }
+}
+
+main().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});