Replaces the plugin-side SOUL.md protocol append: on Bot-Mode-managed
installs (any profile carrying ui_meta['hermes-bots']) the prompt builder
injects the "Messaging other agents" section into every session of every
profile — including headless `hermes -p <bot> chat` sessions a teammate
starts — so bot handoffs work without mutating user-authored SOUL files.
- tools/bot_mode_probe.py: silent-when-unmanaged probe, cached per
(process, home), keyed off the agent's OWN home (not ambient
HERMES_HOME); silent when SOUL.md already carries the legacy section
- agent/system_prompt.py + agent_init.py + config_defaults.py: wired as
agent.bot_mode_protocol (default True), stable tier, byte-stable
across rebuilds (E2E-verified against the real build_system_prompt)
- tui_gateway profiles.list gains bot_mode_protocol capability flag;
the bundled plugin gates ALL SOUL protocol writes on it (backfill,
composeSoul, Edit save) — older gateways keep the SOUL-append path
- overhead: ~916 bytes, only on Bot-Mode installs; zero elsewhere
Supersedes the SOUL backfill half of Hermes-Bot-Mode#99 (credit
@kaduxo — the handle fix, `hermes profile list` correction, and
idempotent-append guards from that PR ship in the bundled plugin).