Combines the local SQLite bridge (getPdbLocal/queryPeeringDBLocal, was at the very top of the file) with the live-API fetch helpers (fetchPeeringDB/ fetchPeeringDBWithRetry/pdbSemaphore, ~950 lines further down) into one module -- they were always one logical unit (queryPeeringDBLocal is only ever called from fetchPeeringDB). Verified via smoke-test harness (28/28 match). server.js: 5018 -> 4827 lines.