feat(typing): added type hints for ASGI Scope dict

[symtalha14]

Summary of Changes

Improve ASGI scope type annotations by introducing TypedDict-based scope definitions. This provides more accurate typing for ASGI scope objects, reduces the need for type: ignore comments, and improves static type checking throughout the ASGI codebase.

Related Issues

#2628

Pull Request Checklist

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• Applied changes to both WSGI and ASGI code paths and interfaces (where applicable).
• Added tests for changed code.
• Performed automated tests and code quality checks by running tox.
• Prefixed code comments with GitHub nick and an appropriate prefix.
• Coding style is consistent with the rest of the framework.
• Updated documentation for changed code.
  • Added docstrings for any new classes, functions, or modules.
  • Updated docstrings for any modifications to existing code.
  • Updated both WSGI and ASGI docs (where applicable).
  • Added references to new classes, functions, or modules to the relevant RST file under docs/.
  • Updated all relevant supporting documentation files under docs/.
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  • Changed/added classes/methods/functions have appropriate versionadded, versionchanged, or deprecated directives.
• Changes (and possible deprecations) have towncrier news fragments under docs/_newsfragments/, with the file name format {issue_number}.{fragment_type}.rst. (Run tox -e towncrier, and inspect docs/_build/html/changes/ in the browser to ensure it renders correctly.)
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (5d46622) to head (efc0ea2).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##            master     #2657   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           64        64           
  Lines         7985      7988    +3     
  Branches      1103      1104    +1     
=========================================
+ Hits          7985      7988    +3     

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