feat(deducer): parse index URLs from requirements.txt

[jianzs]

The deducer now parses index URLs specified in the project's root requirements.txt file. These URLs are utilized for dependency installation and are also included in the generated requirements.txt file.

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

2. What is the scope of this PR (e.g. component or file name):

• Pyright Deducer

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[changeset-bot]

🦋 Changeset detected

Latest commit: d3be593

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@plutolang/pyright-deducer	Patch
@plutolang/cli	Patch

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[Peefy]

LGTM