feat(catalog): disable Gemini 2.5 Pro, add Cerebras zai-glm-4.7

Google moved Pro-tier Gemini off the free tier on 2026-04-01. Cerebras
added z.ai GLM-4.7 (355B) to their free tier, throttled to 10 RPM /
100 RPD with an 8192 context cap while demand stays high.

server/src/db/index.ts

@@ -39,6 +39,7 @@ export function initDb(dbPath?: string): Database.Database {
   migrateModelsV2(db);
   migrateModelsV3Ranks(db);
   migrateModelsV4(db);
+  migrateModelsV5(db);
   ensureUnifiedKey(db);
 
   console.log(`Database initialized at ${resolvedPath}`);
@@ -543,6 +544,35 @@ function migrateModelsV4(db: Database.Database) {
   applyRanks();
 }
 
+/**
+ * V5: Google moved all Pro-tier Gemini off the free tier on 2026-04-01 — disable
+ * gemini-2.5-pro. Add Cerebras `zai-glm-4.7` (355B z.ai GLM preview, newly on
+ * free tier but throttled to 10 RPM / 100 RPD due to high demand; context capped
+ * at 8192 on free tier).
+ */
+function migrateModelsV5(db: Database.Database) {
+  db.prepare(`UPDATE models SET enabled = 0 WHERE platform = 'google' AND model_id = 'gemini-2.5-pro'`).run();
+
+  const insert = db.prepare(`
+    INSERT OR IGNORE INTO models (platform, model_id, display_name, intelligence_rank, speed_rank, size_label, rpm_limit, rpd_limit, tpm_limit, tpd_limit, monthly_token_budget, context_window)
+    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+  `);
+  const apply = db.transaction(() => {
+    insert.run('cerebras', 'zai-glm-4.7', 'GLM-4.7 (Cerebras)', 7, 1, 'Frontier', 10, 100, null, null, '~3M', 8192);
+    const missing = db.prepare(`
+      SELECT m.id FROM models m
+      LEFT JOIN fallback_config f ON m.id = f.model_db_id
+      WHERE f.id IS NULL ORDER BY m.intelligence_rank ASC
+    `).all() as { id: number }[];
+    if (missing.length > 0) {
+      const maxPriority = (db.prepare('SELECT COALESCE(MAX(priority), 0) AS mx FROM fallback_config').get() as { mx: number }).mx;
+      const addFb = db.prepare('INSERT INTO fallback_config (model_db_id, priority, enabled) VALUES (?, ?, 1)');
+      for (let i = 0; i < missing.length; i++) addFb.run(missing[i].id, maxPriority + i + 1);
+    }
+  });
+  apply();
+}
+
 function ensureUnifiedKey(db: Database.Database) {
   const existing = db.prepare("SELECT value FROM settings WHERE key = 'unified_api_key'").get() as { value: string } | undefined;
   if (!existing) {