fix(parameters): honor auto transform in batched get_parameters_by_name

[MohammedAlkindi]

Issue number: closes #8435

transform="auto" infers the transform from the parameter name suffix, but _transform_and_cache_get_parameters_response called transform_value() without key=name. The batched GetParameters path therefore inferred from an empty string and fell back to the identity transform, returning raw strings with nothing raised. Parameters routed through BaseProvider.get() (decrypt=True) already pass the key, so a single get_parameters_by_name call could return a parsed dict for some names and a raw string for others. #7083 fixed the argument-order bug in this function and covered transform="json"; auto was not covered by that test. This was the only transform_value() call site omitting the key: BaseProvider.get() and secrets.py pass it, and get_multiple() transforms a dict keyed per item.

Fail-before, source reverted and the new test kept: 1 failed, the assertion showing the raw JSON string against the expected dict. Pass-after: 1 passed. tests/functional/parameters/: 125 passed. ruff format --check and ruff check: clean.

Not run here: make mypy, make ty, and the e2e suite.

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Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[leandrodamascena]

Thanks for working on this @MohammedAlkindi! Approved.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.65%. Comparing base (78ce2cb) to head (2d75a71).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8436   +/-   ##
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  Coverage    96.65%   96.65%           
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  Files          296      296           
  Lines        14885    14885           
  Branches      1263     1263           
========================================
  Hits         14387    14387           
  Misses         363      363           
  Partials       135      135           

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[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!

[powertools-for-aws-oss-automation]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!