Jaah API reference agent prefix exclusion

reference-data/jaah-api.toml excludes internal routes by plain string prefix `/api/agent`, which also drops the tenant routes `/api/agents*` and `/api/agent-catalog*` (about 11 operations) from the published Jaah API reference. apps/api/test_jaah_api_reference.py (`_INTERNAL_PREFIXES`) asserts the same string prefix. Suggestions: 1. Match internal prefixes on a path-segment boundary (`/api/agent/` or exact `/api/agent`), so `/api/agents` and `/api/agent-catalog` are published. 2. Ensure each newly published operation has a summary and description, and update the test's prefix rule to match. Out of scope: changing any API behaviour; publishing `/api/agent/*` or `/api/node-*` internal routes. Done means: `python3 tools/jaah_api_reference.py --write` lists the agents and agent-catalog tenant operations; `./dc check quick` and the api reference test green.

Exclude prefixes now match at a segment boundary ("-" suffix = family), so 11 Agents operations (/api/agents, /api/agent-catalog, /api/agent-registry) are published with descriptions; test updated. Quick gate + reference test green; PR #6502 queued. Memory: none applied.