Move fleet retention and concurrency controls into Settings

Persist settings in SQLite, import legacy environment values once, and apply changes to cleanup and deployment queues without restarting.

Closes #51

src/lib/server/db/index.ts

@@ -6,6 +6,7 @@ import schemaSql from './schema.sql?raw';
 import { requirement, type BetaPlan, type BetaRequirement } from '../../beta-plan.js';
 import { emptyMetrics } from '../fleet/beta-evaluation.js';
 import { backfillLeaderboard } from '../fleet/leaderboard-ingest.js';
+import { initializeFleetSettings } from './fleet-settings.js';
 
 let _db: Database.Database | null = null;
 
@@ -345,6 +346,7 @@ export function db(): Database.Database {
         migrateGameTelemetry(handle);
         migrateTable(handle, 'leaderboard_matches', [{ name: 'start_players', ddl: 'ALTER TABLE leaderboard_matches ADD COLUMN start_players INTEGER' }]);
         backfillLeaderboard(handle);
+        initializeFleetSettings(handle);
     } catch (err) {
         handle.close();
         throw err;