Simplify SourceHealthMonitor and SourceHealthReset

What Was Built

Simplified the health monitoring subsystem to use a 4-status model (working/failing/declining/improving) instead of the previous 6-status model (healthy/warning/critical/auto_paused/declining/improving). Removed the warning_threshold method, simplified determine_status decision tree, and updated all health classes to use the new status values.

Commits

• 8398a21 refactor(health): simplify determine_status to 4-status decision tree
• 4ddf45f refactor(health): update SourceHealthReset to use working status
• b919ba6 refactor(health): update ImportSourceHealthCheck to new status values

Tasks Completed

1. Rewrote determine_status in SourceHealthMonitor to use 4-status decision tree (working/failing/declining/improving), removed warning_threshold method, simplified healthy_threshold, updated apply_status fallback to "working"
2. Updated SourceHealthReset reset_attributes to use "working" instead of "healthy"
3. Updated ImportSourceHealthCheck Result structs: "healthy" -> "working", "unhealthy" -> "failing"

Files Modified

• lib/source_monitor/health/source_health_monitor.rb
• lib/source_monitor/health/source_health_reset.rb
• lib/source_monitor/health/import_source_health_check.rb

Deviations

None.