WebUI: migrate URL routes from /objects to /data

[nopcoder]

Migrate all internal URL routes from /repositories/:repoId/objects to /repositories/:repoId/data to match the renamed "Data" tab.

This includes:

• Adding /data as the primary route, keeping /objects as a backward-compatible alias
• Updating all internal navigation links across all pages (branches, tags, commits, compare, actions, pulls) to use /data
• Updating the breadcrumb repo link in the layout
• Updating the Data tab nav link
• Updating e2e test goto() calls that use direct URLs

Deferred from #10271 to keep the initial UI redesign focused on visual changes.