Move status validation from post-retrieval checks into Prisma WHERE
clauses. This prevents TOCTOU issues and ensures only ACTIVE
connections are retrieved. Removed redundant status checks after
retrieval in both query and command services.
Security improvement: Enforces status=ACTIVE in database query rather
than checking after retrieval, preventing race conditions.
Fixes#283
Co-Authored-By: Claude Sonnet 4.5 <[email protected]>