v1.5.8 — T-309 partial: click-to-add mit palette + window overlay

Added — visual polish on the T-301 strat editor

• Click-to-add mit palette (web/src/StratEditor.jsx → MitPalette): collapsible panel below the mit-plan table grouping labeled abilities by mit_party / mit_self / mit_boss_debuff. One click adds a slot pre-populated with that ability; the two-step "+ slot then pick from dropdown" flow is now optional. Each pill shows the wiki-scraped duration when present (e.g. "Reprisal · 15s") so picking is informed.
• Visual mit-window overlay (MitWindowOverlay): SVG strip rendered below the mit-plan table for the current mechanic. Vertical red dashed line marks the boss cast at t+0. Each configured slot renders as a colored bar from window_offset_ms to window_offset_ms + duration_ms (wiki-scraped, fallback 15 s). Overlapping mits stack visibly; gaps in coverage are obvious. Bar color tracks expected_role (MT/OT/H1/H2/D1..D4/any). Tick marks at +5s/+10s/+15s/etc. for orientation.
• API: AbilityLabelOut now carries duration_ms (the column was added in v1.5.7 but wasn't surfaced). Strat editor reads it to size overlay bars; consumers that don't care can ignore the field.

Scope (transparent — what's left of T-309)

• Drag-to-reorder of mit slots within a phase timeline is NOT in this ship. PLAN §11 flagged T-309 as 5–10× T-301's build effort with "high UX rework risk if requirements shift". The palette + overlay deliver the two highest-value concrete needs called out in IDEAS (faster slot creation; visible overlap/coverage) without committing to a drag-and-drop control scheme that hasn't been validated by usage. The remaining piece is now scheduled separately as "T-309 drag-to-reorder" in IDEAS, awaiting user feedback on the palette/overlay before further investment.

Tests

• 1 new test in tests/test_ability_labels_api.py: the labels endpoint surfaces duration_ms so the overlay can size its bars.
• 379 tests passing (378 → 379).