feat: v2 - mini content for collapsed docked windows

[maxy-shpfy]

Description

Adds "mini content" support for docked windows that are in a collapsed dock area. When a dock panel is collapsed, each window that has registered mini content renders a compact icon button in the collapsed dock strip. Clicking the button opens a popover showing the full window content without expanding the dock.

• ComponentLibraryWindowMiniContent renders a LayoutGrid icon button as the collapsed representation of the Component Library panel.
• PipelineTreeWindowMiniContent renders a GitBranch icon button with a live validation badge overlay — a green check when the pipeline is valid, or an issue badge showing error/warning counts.
• CollapsedDockWindowMini wraps each mini button in a Radix Popover that displays the full panel content (with title header) when triggered, sized to match the panel's configured width.
• WindowStoreImpl gains a miniContentMap, a setWindowMiniContent action, and a miniContentSignature observable that allows MobX observers to react when mini content entries are added or removed without storing React nodes in observables.
• DockArea renders the list of CollapsedDockWindowMini components in the collapsed strip, filtered to only windows that have registered mini content.
• Both useComponentLibraryWindow and usePipelineTreeWindow pass miniContent when opening a window and call setWindowMiniContent to keep mini content current on subsequent renders (e.g. after hot reload or store rehydration).

Related Issue and Pull requests

Type of Change

• Bug fix
• New feature
• Improvement
• Cleanup/Refactor
• Breaking change
• Documentation update

Checklist

• I have tested this does not break current pipelines / runs functionality
• I have tested the changes on staging

Screenshots (if applicable)

Screen Recording 2026-04-30 at 11.37.07 PM.mov (uploaded via Graphite)

Test Instructions

1. Open the editor and collapse the left dock area.
2. Confirm that the Component Library and Pipeline Structure panels each show a compact icon button in the collapsed strip.
3. Click the Component Library button and verify the full component library content appears in a popover.
4. Click the Pipeline Structure button and verify the full pipeline tree appears in a popover.
5. Introduce a validation error in the pipeline and confirm the issue badge appears on the Pipeline Structure mini button while the dock is collapsed.
6. Resolve all issues and confirm the green check badge appears instead.
7. Expand the dock and confirm normal panel behavior is unaffected.

Additional Comments

Mini content is stored outside MobX observables (in a plain Map) to avoid React element serialization issues. The miniContentSignature counter is used as a lightweight signal to trigger re-renders in observers that need to query the map.

[maxy-shpfy]

• feat: v2 - mini content for collapsed docked windows #2188 👈 (View in Graphite)
• master

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[github-actions]

🎩 Preview

A preview build has been created at: 05-01-feat_v2_-_mini_content_for_collapsed_docked_windows/47416b3