[BUILD] Fixes compiling problems in NDK r27

[owent]

Fixes #3516

Changes

• Fixes compiling problems in NDK r27

For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

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[Copilot]

Pull Request Overview

This PR addresses compilation issues in NDK r27 by reorganizing includes and correcting std::shared_ptr<FILE> usage for file handles.

• Moved the nlohmann/json.hpp include to eliminate duplicates.
• Replaced the invalid std::make_shared<FILE>() with a direct std::shared_ptr<FILE> allocation using fclose as a deleter.

Comments suppressed due to low confidence (2)

exporters/otlp/src/otlp_file_client.cc:1296

• [nitpick] The variable name of is ambiguous; consider renaming it to file_handle or file_ptr for better clarity.

    std::shared_ptr<FILE> of = std::shared_ptr<std::FILE>(new_file, fclose);

exporters/otlp/src/otlp_file_client.cc:1239

• Consider adding a unit test to verify that the file handle is correctly opened and closed under NDK r27 to prevent future regressions.

    }

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.96%. Comparing base (f4897b2) to head (816455b).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3517      +/-   ##
==========================================
+ Coverage   89.95%   89.96%   +0.02%     
==========================================
  Files         219      219              
  Lines        7051     7051              
==========================================
+ Hits         6342     6343       +1     
+ Misses        709      708       -1     

see 1 file with indirect coverage changes

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[marcalff]

LGTM

Commit owned by owent and not by copilot, so eacyCLA is clear here.

Ok to merge, with minor fix on std::FILE versus FILE.

[marcalff]

@owent Thanks for the std fixes. Will merge once CI completes.