feat: M1 admin console — all 10 remaining pages + signal/quality/ops infrastructure

Admin console (issues #63–72):
- Event stream viewer: live-tail ring buffer (500 events) with subject/user filters
- Feature store browser: per-user feature vector history from ml/serving
- Model registry panel: MLflow embed at /admin/models
- Experiment dashboard: LinUCB per-user stats (pulls, reward, θ) + bandit reset
- Recommendation log: per-tip explainability (policy, score, features, latency)
- Reward analytics: daily reaction breakdown + per-policy compare
- Data quality widget: missing-feature rate, stale-token rate, daily completeness
- Ops actions: replay-signal, policy enable/disable; user actions link to Users page
- SQL runner: read-only SELECT runner with saved queries
- Health rollup: fan-out to api/ml/sqlite/event-bus with auto-refresh

Backend:
- tip_scores table: logs features+policy+score+latency at every scoring call (#67)
- saved_queries table: per-admin saved SQL (#71)
- Event bus: 500-event ring buffer + tail() API (#63)
- Admin routes: /events, /tips, /reward-analytics, /data-quality, /health,
  /policies, /replay-signal, /sql, /saved-queries endpoints
- /api/ml/* admin-gated proxy to ml/serving (#64, #66)
- Shadow-policy registry in recommender (#56)

ML serving:
- /reset/{user_id}: clear bandit state + feature history (#66)
- /stats/{user_id}: pulls, cumulative reward, estimated mean, θ (#66)
- /features/{user_id}: last 100 feature vectors logged at scoring time (#64)
- Meta (pulls, rewards) persisted alongside A/b matrices

Web:
- Tip action sheet adds Helpful / Not helpful buttons (#62)
- TipFeedback type extended with helpful/not_helpful actions
- Rewards mapped: helpful=+0.5, not_helpful=−0.5

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

services/api/src/db/index.ts

@@ -8,6 +8,9 @@ sqlite.pragma('journal_mode = WAL');
 sqlite.pragma('foreign_keys = ON');
 
 export const db = drizzle(sqlite, { schema });
+// Raw sqlite client — used by the SQL runner endpoint.
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export const rawSqlite: any = sqlite;
 
 export function runMigrations() {
   sqlite.exec(`
@@ -17,6 +20,7 @@ export function runMigrations() {
       name TEXT,
       image TEXT,
       google_id TEXT UNIQUE,
+      role TEXT NOT NULL DEFAULT 'user',
       consent_given INTEGER NOT NULL DEFAULT 0,
       consent_at TEXT,
       created_at TEXT NOT NULL,
@@ -43,11 +47,72 @@ export function runMigrations() {
       created_at TEXT NOT NULL
     );
 
+    CREATE TABLE IF NOT EXISTS tip_views (
+      id TEXT PRIMARY KEY,
+      user_id TEXT NOT NULL REFERENCES users(id),
+      tip_id TEXT NOT NULL,
+      served_at TEXT NOT NULL
+    );
+
+    CREATE TABLE IF NOT EXISTS push_subscriptions (
+      id TEXT PRIMARY KEY,
+      user_id TEXT NOT NULL REFERENCES users(id),
+      endpoint TEXT NOT NULL UNIQUE,
+      p256dh TEXT NOT NULL,
+      auth TEXT NOT NULL,
+      created_at TEXT NOT NULL
+    );
+
     CREATE TABLE IF NOT EXISTS sessions (
       id TEXT PRIMARY KEY,
       user_id TEXT NOT NULL REFERENCES users(id),
       expires_at TEXT NOT NULL,
       created_at TEXT NOT NULL
     );
+
+    CREATE TABLE IF NOT EXISTS admin_actions (
+      id TEXT PRIMARY KEY,
+      admin_id TEXT NOT NULL REFERENCES users(id),
+      action TEXT NOT NULL,
+      target_type TEXT,
+      target_id TEXT,
+      detail TEXT,
+      created_at TEXT NOT NULL
+    );
+
+    CREATE TABLE IF NOT EXISTS tip_scores (
+      id TEXT PRIMARY KEY,
+      user_id TEXT NOT NULL REFERENCES users(id),
+      tip_id TEXT NOT NULL,
+      policy TEXT NOT NULL,
+      ml_score INTEGER,
+      features_json TEXT,
+      candidate_count INTEGER,
+      latency_ms INTEGER,
+      served_at TEXT NOT NULL
+    );
+
+    CREATE TABLE IF NOT EXISTS saved_queries (
+      id TEXT PRIMARY KEY,
+      admin_id TEXT NOT NULL REFERENCES users(id),
+      name TEXT NOT NULL,
+      sql TEXT NOT NULL,
+      created_at TEXT NOT NULL
+    );
   `);
+
+  // Additive column migrations — safe to run on existing DBs.
+  // SQLite doesn't support IF NOT EXISTS on ALTER TABLE; we ignore the error if already present.
+  for (const stmt of [
+    `ALTER TABLE users ADD COLUMN role TEXT NOT NULL DEFAULT 'user'`,
+    `ALTER TABLE push_subscriptions ADD COLUMN created_at TEXT NOT NULL DEFAULT ''`,
+  ]) {
+    try { sqlite.exec(stmt); } catch { /* column already exists */ }
+  }
+
+  // Seed first admin from env (ADMIN_SEED_EMAIL).
+  const seedEmail = process.env.ADMIN_SEED_EMAIL;
+  if (seedEmail) {
+    sqlite.prepare(`UPDATE users SET role = 'admin' WHERE email = ? AND role = 'user'`).run(seedEmail);
+  }
 }