The HERMES_AGENT_HELP_GUIDANCE block (added #16535) only fired when the
user explicitly asked about configuring/setting up Hermes. Broaden it so
the agent treats the docs as a standing source of self-knowledge for any
Hermes-related help and for understanding its own features/tools, points
to the hermes-agent skill for additional guidance, and treats the docs as
the authoritative/latest source of truth when the two differ.
Static constant in the cache-safe stable tier — no prompt-cache impact.