fix: use Array.at(-1) to extract repo name from URL

[tmdeveloper007]

Closes #498.

Summary of What Has Been Done:
Replaced the length check and pop() pattern with Array.at(-1) for extracting repo name from URL, as suggested by the maintainer. This is simpler and has no edge cases.

Changes Made:

• File: src/lib/github.ts
• Changed from to

Impact it Made:

• Simpler code with no fallback to full URL edge case
• Uses the recommended Array.at(-1) approach

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