fix(deducer): correct package directory resolution and METADATA parsing

[jianzs]

This commit addresses two separate issues identified in the deducer:

• The deducer incorrectly searched for distribution information within the stub type directory, which lacks the required dist info. The resolution has been updated to check for the presence of nonStubImportResult within the ImportResult. If present, it is now utilized to determine the correct package directory.
• The parsing of the dist-info/METADATA file was flawed due to the possibility of encountering multiple Name lines. The parser has been adjusted to only consider lines that begin with Name: and are not preceded by any spaces.

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: d6b477c

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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