Cron now resolves its toolset from the same per-platform config the
gateway uses — `_get_platform_tools(cfg, 'cron')` — instead of blindly
loading every default toolset. Existing cron jobs without a per-job
override automatically lose `moa`, `homeassistant`, and `rl` (the
`_DEFAULT_OFF_TOOLSETS` set), which stops the "surprise $4.63
mixture_of_agents run" class of bug (Norbert, Discord).
Precedence inside `run_job`:
1. per-job `enabled_toolsets` (PR #14767 / #6130) — wins if set
2. `_get_platform_tools(cfg, 'cron')` — new, the blanket gate
3. `None` fallback (legacy) — only on resolver exception
Changes:
- hermes_cli/platforms.py: register 'cron' with default_toolset
'hermes-cron'
- toolsets.py: add 'hermes-cron' toolset (mirrors 'hermes-cli';
`_get_platform_tools` then filters via `_DEFAULT_OFF_TOOLSETS`)
- cron/scheduler.py: add `_resolve_cron_enabled_toolsets(job, cfg)`,
call it at the `AIAgent(...)` kwargs site
- tests/cron/test_scheduler.py: replace the 'None when not set' test
(outdated contract) with an invariant ('moa not in default cron
toolset') + new per-job-wins precedence test
- tests/hermes_cli/test_tools_config.py: mark 'cron' as non-messaging
in the gateway-toolset-coverage test
ef5eaf8d87