Complete the config hot-reload flow:
- ServiceManager receives ConfigReloadRequest from HTTP plugin
- Reloads config from source_path using AppConfig::from_file
- Updates internal config Arc
- Broadcasts ConfigReloaded(new_config) to all plugins
- Logs error on reload failure without crashing
This closes the P0 gap identified by architect Wang Siyuan:
the HTTP /api/config save endpoint promised hot-reload but
ServiceManager only had a TODO placeholder.
cargo check: 0 warnings, cargo test: 22/22 passed
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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