Replace flat watcher.rs with watcher/ module containing mod.rs plus stub
sub-modules for journald, kmsg, and inotify. Upgrades spawn() to accept
log_paths and return mpsc::Receiver<SystemEvent>. Updates lib.rs call site.
- load() now rejects patterns with empty match_text or empty sources list
- EventSource derives Serialize/Deserialize with serde tag for emit() readiness
- AppLog variant changed to struct form (AppLog { app }) for tagged enum compat
- classify() takes &SystemEvent directly (top-level use import, not per-fn)
- #[must_use] on classify()
- 5 new tests: any-source wildcard (journald+kmsg), applog mismatch, empty-field validation
Add EventSource enum and update SystemEvent in watcher.rs (M0 stub
updated to support Task 5 clean deletion). Create patterns.rs with
PatternFile/Pattern/MatchedEvent types, TOML loader, and classify()
matching against source + text. Five unit tests covering journald,
applog, no-match, and source discrimination cases.
- parse_id now strips both double and single quotes per os-release spec
- distro_family debian arm includes "mint" (legacy Linux Mint ID)
- Add tests: single-quoted ID round-trip, mint family classification
