feat!: rename FaceImage class to FaceImagePayload & remove ReadMemberLayoutAsync overload

[nogic1008]

close #403

[Copilot]

Pull Request Overview

This PR renames the FaceImage class to FaceImagePayload and removes a method overload for ReadMemberLayoutAsync to improve API clarity and naming consistency.

Key changes:

• Renamed FaceImage entity class to FaceImagePayload for better semantic clarity
• Removed the parameterless ReadMemberLayoutAsync() overload in favor of a single method with default parameters
• Updated all references, tests, and API documentation to reflect the new naming

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
FaceImagePayload.cs	Renamed the record class from FaceImage to FaceImagePayload
KaonaviClient.Member.cs	Updated method signatures to use FaceImagePayload instead of FaceImage
KaonaviClient.Layout.cs	Removed overload method and added default parameter value
Context.cs	Updated JSON serialization context for the renamed class
PublicAPI files	Updated API surface documentation for breaking changes
Test files	Updated test class names and references to use new FaceImagePayload name
Program.cs	Updated sample code to use explicit parameter naming

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.72%. Comparing base (b70f63a) to head (5029e5b).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #405      +/-   ##
==========================================
- Coverage   97.72%   97.72%   -0.01%     
==========================================
  Files          41       41              
  Lines         616      615       -1     
  Branches       58       58              
==========================================
- Hits          602      601       -1     
  Misses          5        5              
  Partials        9        9              

Flag	Coverage Δ
ARM64	97.72% <100.00%> (-0.01%)	⬇️
Linux	97.72% <100.00%> (-0.01%)	⬇️
X64	97.72% <100.00%> (-0.01%)	⬇️
macOS	97.72% <100.00%> (-0.01%)	⬇️

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