Bound and exhaust Content document discovery - #2659

Code Review Summary

PR #2659 bounds Content document discovery with deterministic, access-scoped pagination, explicit totals/continuations, exact-title filters, and a shared predicate used consistently by count and page queries. The UI now exhausts list pages before exposing the document tree and rejects missing, inconsistent, duplicated, or non-advancing pagination metadata rather than treating a clipped response as complete. The optimistic cache contract remains object-shaped internally while consumers continue to receive a document array.

Risk: Standard — this changes shared discovery/business logic and privacy-sensitive filtering, though it does not alter authentication or public API security boundaries.

No confirmed high- or medium-severity issues were found. The implementation has strong coverage for multi-page list/search results, exact-match cardinality, outsider isolation, soft-deleted database filtering, stable-key projection replay, and optimistic cache compatibility. Code-review agents also verified the relevant Content tests pass.

🧪 Browser testing: Skipped — dev server was available, but browser automation tooling was unavailable to all executors; backend endpoints were independently verified, while UI flows could not be exercised.