docs: archive changelog for v0.7.12 [skip ci]

Author: github-actions[bot]

.changelog/v0.7.x.md .changelog/v0.7.12.md.changelog/v0.7.x.md renamed to .changelog/v0.7.12.md

@@ -1,4 +1,4 @@
-# Release v0.7.x - Migration Map, AI Discovery Improvements
+# Release v0.7.12 - Migration Map, AI Discovery Improvements
 
 Released: Unreleased
 
@@ -23,7 +23,7 @@ This release improves the AI Discovery feature with dismiss functionality, debug
 - GET `/api/ai-discovery/debug/runs/:runId` - detailed run info including prompt preview and output
 - Error details capture (last 10 lines of stderr/stdout) stored on failed runs
 
-### Migration Map Visualization (v0.7.x)
+### Migration Map Visualization (v0.7.12)
 - New 6th tree view mode: "Migration Map" plots ancestors on an interactive world map
 - Leaflet.js map with OpenStreetMap/CartoDB dark tiles
 - Lineage-colored markers (paternal=blue, maternal=red) with generation depth variation