Phase 1: data pipeline (Postgres+Redis with in-memory fallback, mock telemetry publisher, WebSocket fan-out, hub /debug page)

- packages/db: postgres.js + ioredis wrapper, StateStore interface with
  InMemory + Postgres implementations, schema migration runner
- apps/api: refactored to use @kerbal-rt/db; live WebSocket hub subscribes
  to store changes and broadcasts to all clients
- apps/tools/mock-telemetry: Node script that generates realistic KSP
  state and POSTs to /api/v1/ingest at 1Hz (uses same keplerian math
  as the live-map renderer)
- apps/hub: new /debug page that connects to /api/v1/live and shows
  the live state
- ksp/README.md: documents Phase 1c (real kRPC bridge) and the two
  implementation options
- Tests: 17 total (5 kepler math, 5 db store, 5 API health/state,
  2 API WebSocket fan-out)

End-to-end verified: mock publisher → API → hub /debug page,
11 snapshots/5s over WebSocket, vessels advancing in mean anomaly.

packages/db/src/config.ts

@@ -0,0 +1,45 @@
+/**
+ * Configuration helpers for the db package.
+ *
+ * Reads from environment variables. Throws clearly if a required var
+ * is missing.
+ */
+
+export interface DbConfig {
+  /** Postgres connection URL, e.g. postgres://user:pass@host:5432/db */
+  databaseUrl: string;
+  /** Redis connection URL, e.g. redis://host:6379 */
+  redisUrl: string;
+  /** When true, callers should use the in-memory fallback instead. */
+  useInMemory: boolean;
+}
+
+const REQUIRED_FOR_DB = ['DATABASE_URL', 'REDIS_URL'] as const;
+
+export function loadConfig(env: NodeJS.ProcessEnv = process.env): DbConfig {
+  const databaseUrl = env.DATABASE_URL;
+  const redisUrl = env.REDIS_URL;
+  // Allow opt-out for dev (e.g. when Docker isn't available)
+  const forceInMemory = env.USE_IN_MEMORY === '1' || env.USE_IN_MEMORY === 'true';
+
+  if (forceInMemory) {
+    return { databaseUrl: '', redisUrl: '', useInMemory: true };
+  }
+
+  const missing = REQUIRED_FOR_DB.filter((k) => !env[k]);
+  if (missing.length > 0) {
+    // Don't crash on import — let the caller decide. The API's
+    // bootstrap() logs a warning and falls back to in-memory mode.
+    return {
+      databaseUrl: databaseUrl ?? '',
+      redisUrl: redisUrl ?? '',
+      useInMemory: true,
+    };
+  }
+
+  return {
+    databaseUrl: databaseUrl!,
+    redisUrl: redisUrl!,
+    useInMemory: false,
+  };
+}