[O13] Error Detection & Reporting

[cjpillsbury]

Detect and report errors gracefully. Basic for V1.

Acceptance Criteria

• Detect network errors
• Detect format errors
• Detect media API errors
• Emit error events
• Graceful failure (stop playback, emit error)
• Unit tests with ≥80% coverage

Dependencies

Depends on: #388 (O1), #415 (O7)

Technical Notes

Files: packages/spf/src/core/error/error-detection.ts
Basic error detection, not sophisticated recovery.

Bundle Size Impact

Target: <2KB