feat(visualization): redesign node context menu (#4492)

Migrate the node context menu from ui/nodeContextMenu (Material, CDK
overlay, SCSS) to features/nodeContextMenu following the new feature
architecture: standalone OnPush components with signals, DaisyUI
templates, ngrx confined to stores/ and selectors/.

- Header row shows the node name and copies its path without the
  leading root segment on click
- New "Show in Explorer" action (map right-clicks only) expands the
  File Explorer, scrolls to the node, and briefly highlights it via
  the new ExplorerRevealService
- rightClickedNodeData state gains an origin field to distinguish
  map and explorer right-clicks
- Folder color row keeps the five marking colors, adds a clear button
  for custom colors, and reuses the inline color picker, which moved
  to features/shared with a new brush-trigger variant
- Unflatten entry shows the flatten icon rotated 180 degrees

Co-authored-by: Christian Hühn <christian.huehn@maibornwolff.de>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>