Add KER Evidence Quality Distribution visualization

[marvinm2]

Description

Visualize the distribution of Key Event Relationship (KER) evidence scores across different assessment dimensions including biological plausibility, empirical support, and uncertainty. This shows data quality maturity and helps identify KERs needing evidence strengthening - essential for OECD endorsement readiness.

Visualization Types

• Latest snapshot: Current evidence quality distribution
• Historical trends: Evolution of evidence quality over time

Value & Priority

• Priority: Phase 1 - High Priority
• Value: High (critical for OECD endorsement)
• Complexity: Low

Implementation Details

Key Data Requirements

Available properties from property_labels.csv:

• has_evidence (Assessment category)
• Biological Plausibility (C80263)
• Empirical Support (data_2042)
• Uncertainty (C71478)

Extract and count KERs by evidence level (high/moderate/low) for each dimension.

Visualization Format

• Latest view: Stacked bar chart showing KER counts by evidence level across dimensions
• Trends view: Stacked area chart showing evidence quality evolution
• Cross-tabulation: Evidence levels by OECD status (optional enhancement)

Expected Insights

• Identify KERs with weak evidence that need strengthening
• Track overall evidence quality improvements over time
• Guide curation priorities for OECD submission
• Understand correlation between evidence quality and OECD approval status
• Support quality assurance and review processes

Performance Notes

• Simple property aggregation queries
• Low complexity, should be very performant
• Can leverage existing property filtering patterns
• Consider creating separate views for each evidence dimension