Create an isometric editor

[cnotv]

As a new attempt to populate maps, update SceneEditor to be an isometric editor.

Improve the UX for the elements panel:

• .elements-panel__filter-bar buttons should be ghost
• .elements-panel__add-label
  • should have no "Add" prefix
  • should have a more prominent add button, with better wording:
    • New camera
    • Add model
    • Add image

It should be possible to place images directly on the ground with a click. You may consider a palette of loaded images to be used as a brush to define the coordinates of stamped clones.

[cnotv]

Implementation Plan

1. Isometric camera default

Set SceneEditor default camera to isometric (orthographic at 45° angle), position [20, 20, 20] looking at origin.

2. Elements panel UX

• Filter-bar buttons → ghost variant
• Remove 'Add' label prefix; rename to 'New camera', 'Add model', 'Add image'
• More prominent add buttons

3. Image stamp on ground click

• Image palette in elements panel showing loaded textures
• Selecting an image enters stamp mode
• Canvas click → ray vs ground plane (y=0) → place mesh clone at hit position

Files: SceneEditor.vue, ElementsPanel.vue, config.ts