1b51ad5f89
mem0ai declared pg as a required peer pinned to exactly 8.11.3, so npm auto-installed it for every user (including hosted MemoryClient users) and failed with ERESOLVE in any project already on a newer pg. The pin existed because pgvector.ts imported pg at module load, so mem0ai/oss crashed without it. PGVector now loads pg through loadPeer on initialize(), like the other optional vector stores, which lets pg and @types/pg become optional ^8.11.x peers. @types/jest moves from peer to dev dependencies. Closes #3307