PR_26179_CHARLIE_029-sprites-clear-reset-controls

[ToolboxAid]

Summary

• Add Clear Canvas and Reset to 16x16 controls to Sprite Creator.
• Keep editor state unsaved and page-session only.
• Preserve no DB/API/schema/persistence behavior.

Validation

• PASS: node --check assets/toolbox/sprites/js/index.js
• PASS: node --check dev/tests/playwright/tools/SpritesToolShell.spec.mjs
• PASS: git diff --check for touched runtime/test files
• PASS: targeted Sprite Creator Playwright shell test

Artifact

• dev/workspace/zip/PR_26179_CHARLIE_029-sprites-clear-reset-controls_delta.zip