feat: allow many-to-one region mapping and multi-territory drill-down

[AdnanQuazi]

Overview

Resolves an issue where users could only map a single territory to a target region on Map charts (e.g., mapping South India -> India blocked mapping North India -> India or West India -> India). Previously, mapping multiple territories resulted in region selection disappearing from the UI, and the map click index overwritten previous mappings so drill-down only queried the last-mapped territory (WHERE territory = 'West India').

This PR removes the 1-to-1 UI restriction and updates the map chart indexing engine (locationRowIndex) to accumulate all matching raw values. When a map polygon with multiple mapped territories is clicked, the drill-down query dynamically upgrades the exact-match (=) filter to an in filter matching against the raw schema column name (WHERE territory IN ('South India', 'North India', 'West India')).

Key Changes

• CHARTS (RegionMappingDialog.vue): Removed usedRegions restriction in getOptions() so users can select and map multiple dataset locations/territories to the same target map region.
• CHARTS (ChartRenderer.vue): Updated locationRowIndex from single-row overwriting to storing { firstRow, rawValues: Set<string> } per map region. Updated handleMapChartClick to upgrade the drill-down query's dimension filter from = to in using the stable schema column (mapConfig.location_column.column_name) when multiple raw values resolve to the clicked map region.

Closes #1085

[mergify]

Tick the box to add this pull request to the merge queue (same as @mergifyio queue).

• Queue this pull request

[greptile-apps]

Confidence Score: 5/5

Change is safe to merge; the fresh-query pattern in getDrillDownQuery makes the in-place filter mutation side-effect-free, and the logic correctly handles single- and multi-territory regions.

The filter mutation targets a freshly-created query object each time, the rawValues Set correctly de-duplicates and accumulates territories under a shared mapped region, and the !mutated guard prevents returning a stale single-territory query when the filter structure doesn't match expectations.

No files require special attention.

_{Reviews (2): Last reviewed commit: "fix: return null when no matching filter..." | Re-trigger Greptile}

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 47.70%. Comparing base (83bcccf) to head (0b79ef6).
⚠️ Report is 54 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1243      +/-   ##
===========================================
- Coverage    47.91%   47.70%   -0.22%     
===========================================
  Files           76       76              
  Lines         5998     6002       +4     
===========================================
- Hits          2874     2863      -11     
- Misses        3124     3139      +15     

Flag	Coverage Δ
server	47.70% <ø> (-0.22%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.