Descript-style word timing, Split, and clip trim on the timeline

[wassgha]

Summary

Adds a more flexible editing paradigm inspired by Descript: transcript stays primary, but the timeline can refine word timing and split/trim clips independently of whole-word deletes.

What’s new

Word timing (fixes ASR bleed)

• Zoomed wordbar chips with draggable start/end handles
• Expanding a word steals time from neighbors so deleting uh no longer eats into hello
• Drag gestures coalesce into a single undo step

Split at playhead

• Timeline Split button + S shortcut insert a scene boundary
• Amber markers on the timeline; double-click to join
• Keep ranges subdivide into selectable clips

Clip trim

• Hover/select a clip to reveal indigo in/out handles
• Dragging creates manual cuts merged with word-derived cuts for preview + export
• Expanding a trim can shrink manual cuts and restore fully covered deleted words

Data model

• ManualCut[] + SceneBoundary[] alongside Word[]
• Undo/redo snapshots all three; persisted in IndexedDB projects
• getCutRanges(words, duration, manualCuts) drives preview and export

Test plan

• Transcribe (or import) media; zoom timeline until word chips show handles
• Drag uh’s left edge right so it no longer overlaps hello, then Cut — hello audio remains
• Press S / Split on a kept region; amber boundary appears; two clips selectable
• Drag clip trim handles; red cut region updates; playback skips the trim
• Undo/redo restores a full drag as one step
• Export includes word cuts + manual trims
• Reload saved project; splits and manual cuts restore
• npx tsx scripts/edits-test.ts passes

  

[wassgha]

Superseded by #31