[v6] Release Preparation & Size Budget

[jessehouwing]

Scope: Ensure extension size within Marketplace limits and prepare preview release.
Acceptance Criteria:

• Size measurement script integrated in CI.
• Dependency pruning list documented.
• Preview publish test successful.
  Tasks:
• Implement size check script.
• Analyze dependency sizes & remove bloat.
• Run preview publish to test org.
  Labels: enhancement