Add comprehensive model tracking across all OTEL metrics and logs:
- Node execution metrics now include model_name for LLM operations
- Suggested question metrics include model_provider and model_name
- Dataset retrieval captures both embedding and rerank model info
- Updated DATA_DICTIONARY.md with complete metric label documentation
This enables granular cost tracking, performance analysis, and usage monitoring per model across all operation types.
Separate background/configuration instructions from the data dictionary:
- README.md: Overview, configuration, correlation model, content gating
- DATA_DICTIONARY.md: Pure reference format with signals and attributes
The data dictionary is now concise (465 lines vs 911) and focuses on
attribute types and relationships without verbose explanations.
- Add dify.credential.id to node execution events
- Add dify.event.id to all telemetry events (APP_CREATED, APP_UPDATED, APP_DELETED, FEEDBACK_CREATED)
This ensures all .name fields have corresponding .id fields for reliable aggregation and deduplication.
- Add APP_CREATED, APP_UPDATED, APP_DELETED counters to EnterpriseTelemetryCounter
- Create EnterpriseTelemetryEvent StrEnum for type-safe event names
- Update metric_handler to use new app-specific counters with labels (tenant_id, app_id, mode)
- Convert all event_name strings to EnterpriseTelemetryEvent enum values
- Update exporter to create OTEL meters for new app counters (dify.app.created.total, etc.)
- Update tests to verify new counter behavior and enum usage
