Diversify service examples and document notify_on_check

[dcellison]

Summary

• Service examples: Replace Brave Search (redundant with Perplexity) with OpenWeatherMap and ntfy to show the service layer works for more than just web search. Keeps Jina Reader and SearXNG.
• notify_on_check docs: Add the missing field to the CLAUDE.md API reference so inner Kai actually knows the feature exists. Includes protocol update and curl example.
• Perplexity notes: Clarify sonar vs sonar-pro model selection in services.example.yaml.

Files changed

File	Change
services.example.yaml	Replace Brave with OpenWeatherMap + ntfy, update Perplexity notes
workspace/.claude/CLAUDE.md	Add notify_on_check to API fields, protocol docs, and example

Test plan

• make check -- lint + format clean
• CI passes