Fix support absolute GitHub URLs in path parser

[envico801]

Fix: Handle absolute GitHub URLs in file links

This PR fixes an issue where file sizes could incorrectly display as "..." when browsing certain forks or navigating through GitHub's SPA interface.

Root cause

The extension currently assumes GitHub file links are always relative URLs:

/owner/repo/tree/main/path/to/file

However, GitHub sometimes injects absolute URLs into the DOM instead:

https://github.com/owner/repo/tree/main/path/to/file

get-path-object.ts parses paths using index-based splitting:

const paths = path.split('/');
const rawPath = paths.slice(5)?.join('/');

This works for relative paths:

["", "owner", "repo", "tree", "main", "src"]

but fails for absolute URLs:

["https:", "", "github.com", "owner", "repo", "tree", "main", "src"]

Because the indices shift, the parser extracts invalid paths such as:

tree/main/src

instead of:

src

This causes repository tree lookups to fail, resulting in "..." placeholders.

This can be reproduced with:

• meson/test cases at main • frida/meson

---

Solution

Normalize all incoming URLs before parsing.

If the path is absolute:

• extract only the pathname using URL.pathname
• preserve the existing relative-path parsing logic

if (path.startsWith('http') || path.startsWith('//')) {
  path = new URL(path, window.location.origin).pathname;
}

This guarantees consistent parsing regardless of how GitHub renders the link.

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⚠️ Important

This PR assumes that #246 is already merged or will be, so part of that PR is present on this one, due to both touching the same file.

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Before:

After: