feat(webhooks): add project event filters

[phucnguyen1707]

Summary

• normalize event filters on webhook creation by trimming, deduplicating, and defaulting blank lists to a wildcard
• reject malformed event names and persist the canonical filter list
• keep normal dispatch subscription-aware while letting authenticated test sends reach every active project endpoint

Tests

• bun test tests/webhook-events.test.mjs tests/project-webhook-management.test.mjs — 11 passed
• full Node test suite — 169 passed
• npx tsc --noEmit
• npm run build