feat(analytics): Enhance timeline charts and add table filtering

[oidacra]

Summary

Enhances analytics dashboard with improved timeline chart data visualization and table filtering capabilities for conversion tracking.

Changes Made

Data Visualization

• Fixed missing data points in timeline charts (analytics-data.utils.ts)

  • Implemented generic fillMissingDates function with factory pattern
  • Added entity factories: createEmptyPageViewEntity, createEmptyConversionTrendEntity, createEmptyTrafficVsConversionsEntity
  • Zero values now display as visible green dots instead of gaps in charts
  • Applied to Conversion Trend, Traffic vs Conversions, and Page View charts

• Updated Traffic vs Conversions chart

  • Changed from "conversion rate %" to absolute "conversions" count for clearer comparison

Table Filtering

• Content Conversions Table (dot-analytics-content-conversions-table.component.*)
  • Added event type multi-select filter with badges
  • Added title/content text search filter
  • Implemented dynamic filter options based on actual data

Testing

• Added 142 lines of unit tests for date gap filling logic
• Comprehensive coverage for all entity types and edge cases

Technical Details

Refactored date gap filling to use a generic factory pattern, eliminating code duplication:

fillMissingDates<T extends TimelineEntity>(
    data: T[], timeRange: TimeRangeInput,
    granularity: Granularity, createEmptyEntity: EmptyEntityFactory<T>
): T[]

Charts now distinguish between "no data" (gaps) and "zero values" (visible points) using conditional styling.

Breaking Changes

None

Testing

• Unit tests added (date filling, factories, entity structures)
• Integration tests verified (store features)
• Manual testing performed (charts, filters, UI)

Related Issues

Fixes #33846