Review: memory prompt conditional lookup

Implementation reviewed on branch memory-prompt-conditional-lookup.

Reviewed commits:

Verdict: approve.

Summary:

Prompt rendering now gates normal memory/knowledge guidance according to available tool capabilities.
Memory-disabled prompt rendering does not advertise memory tools.
Partial-capability rendering avoids naming unavailable memory or knowledge tools.
Normal Pod guidance now encourages somewhat more proactive small targeted lookup when prior decisions, rationale, durable preferences, tickets, policy, workflow, or project history may affect the response or action.
Existing cautions remain: memory can be stale; current authoritative state lives in user instructions, repository files, tickets, git history, and session logs; memory should not be queried mechanically every turn; mutation tools are restricted.
Internal memory extraction/consolidation worker prompts remain isolated from normal Pod guidance.

Review notes:

Initial review requested one blocker fix because cargo test -p pod prompt:: emitted a new unused append_trailing_section warning.
Follow-up commit 3a0c8e1 removed the warning-producing helper path and adjusted partial-capability wording.
Final focused review approved the follow-up. cargo test -p pod prompt:: passed with 53 passed; 0 failed; only an existing unrelated llm-worker dead-code warning remains.

Merge readiness: ready to merge.