Fix Segment anchor tooltips and Editor theme

[stef-k]

Summary

• show active Segment badge tooltips such as A — Start — Ella
• preserve ordered descriptions for same-Place and collision-combined badges
• escape badge descriptions at the Editor and Viewer renderer boundary
• reuse trip-rich-tooltip for Editor dark-theme parity
• retain pointer-only badge hover, non-keyboard behavior, placement, selection ownership, and print rendering

Fixes #489

Validation

• focused resolver/renderer selection: 29 passed
• complete client suite: 92 passed
• TypeScript typecheck: passed
• frontend production build: passed (existing chunk-size warning only)
• built-asset smoke: passed
• LOC policy: passed; existing warnings only
• git diff --check: passed

Screenshots

The change is limited to hover tooltips and dark-theme tooltip styling. No fresh mounted-browser screenshot was produced; deterministic resolver/renderer coverage exercises the corrected production seams.

Database notes

No database, migration, API, or persisted-data changes.