🐛 Resolve renamed workspace aliases by repository identity

[tjakoen]

Change

Resolve redirected workspace names to a canonical workspace only when current GitHub metadata confirms one physical repository and the readable receipt text matches across all aliases. Genuine duplicate repositories and unreadable or differing receipt evidence remain held.

Evidence

• Focused actual-loader checks cover renamed aliases, distinct repository IDs, differing receipts and missing receipts.
• Independent static review cleared the repair after the missing-receipt guard was added.
• The focused live read restored all nine affected joins without changing scores.
• Browser regression completed successfully across the demo views.
• Syntax, public hygiene and whitespace checks passed.

No grade, private identity data or student delivery is included.