[repstein2]

Large manual IRRDB refreshes can exceed HTTP request limits. Repeated requests can start competing imports and cause database lock timeouts. Prefix listings also load and render the entire result set.

This patch adds:

• An optional dedicated background queue without changing the global queue default.
• Duplicate-request protection and serialized member/type imports.
• Batched database inserts and deletes.
• Database pagination with 100 entries per page.
• Bounded change previews with exact totals.
• Updates limited to the requested address family.
• Failure reporting with transaction rollback.

Worker setup is documented in IRRDB-QUEUE.md.

Validation:

• PHP 8.4 syntax checks and isolated regression checks passed, including batching, duplicate dispatch, rollback, requested-family handling, and pagination/template rendering.
• A 10,000-prefix fixture used 10 insert statements and completed in approximately 0.16 seconds.
• Deployed at FL-IX, CIX-ATL, and CIX-NoVA, with successful live refreshes in all three markets.
• A large IPv4 listing containing 862,942 prefixes now returns 100 rows per page.
• No BGP reloads were performed during validation.

Outstanding before acceptance:

• Upstream CI PHPUnit suites passed: 776 tests, 3,652 assertions (Dusk is a separate workflow).
• Psalm passed using the repository baseline. Validation run: https://github.com/repstein2/IXP-Manager/actions/runs/42424224381
• INEX acknowledgement of CLA. Signed agreement and public key emailed to operations@inex.ie on November 7, 2026.
• Companion documentation submitted: Document optional background IRRDB updates and large listings ixp-manager-docs-md#32 (mkdocs build passed).

Ready for maintainer review and feedback on queue configuration, locking, and pagination/search behavior. Existing authorization checks are retained. The existing GET update endpoint is unchanged.