Make labels consistent in OneDesign Plugin

[vishal4669]

Description

Currently, the labeling for sites in the OneDesign Plugin is inconsistent. To maintain clarity and uniformity across OnePress Ecosystem, update the labels as follows:

• Use “Governing Site” for Main sites
• Use “Brand Sites” for Consumer sites

Acceptance Criteria

• Update all plugin references to use the new labels
• Ensure labels are reflected consistently in the UI, documentation, and code comments
• Verify no outdated terminology remains