Keep avatar clear of toolbar via pure CSS layout (#131)

[ArthurArthurArthur0817]

Overview

Alternative proof-of-concept for #131 (and related to PR #244).

Solution

To keep the layout logic lightweight without adding a runtime listener, this approach achieves the fix using pure CSS:

1. Move <aside id="jim-stage"> inside <div class="editor-stack">.
2. Set .editor-stack { position: relative; }.
3. Update .jim-stage to top: 0.5rem; anchored to the editor stack.

When .editor-toolbar wraps into two rows, the browser's native document flow automatically pushes .editor-stack and the avatar down, keeping the Run tests button completely visible and clickable.

Testing

• Verified locally at ~1220px width where .editor-toolbar wraps into two rows.
• Verified that no JavaScript listeners are required.

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Summary by cubic

Fixes the avatar overlapping the toolbar when the toolbar wraps to two rows, using pure CSS instead of a runtime listener.

• Moves #jim-stage inside .editor-stack and changes .jim-stage from position: fixed to position: absolute, so it anchors to .editor-stack (now position: relative) instead of the viewport.
• The browser's native flow pushes the stage down when the toolbar wraps, keeping the Run tests button visible and clickable.
• Aligns the stage markup's indentation with the project's gate rules.

^{Written for commit c86ebb1. Summary will update on new commits.}

[jserv]

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