Exclude private/protected fields from source generators

[MatthewSteeples]

Private and Protected fields can't be set from extension methods so the current implementation will fail to compile if your class contains either of these.

This fix excludes them from the source generation.

[Copilot]

Pull request overview

This PR updates the FastCloner source generator to avoid generating clone code that would not compile when a clonable type contains non-accessible fields (private/protected), and adds regression tests covering those edge cases.

Changes:

• Exclude private and protected members from source-generator member collection to prevent invalid generated assignments.
• Add source-generator edge case tests verifying private/protected fields are skipped (and thus remain default on the clone).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
src/FastCloner.SourceGenerator/MemberCollector.cs	Skips private/protected members during member collection for generated clone code.
src/FastCloner.Tests/SourceGeneratorEdgeCaseTests.cs	Adds tests ensuring private/protected fields do not participate in source-generated cloning.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[lofcz]

@MatthewSteeples thanks for the contribution. I won't be merging this, since FastCloner by default should fully clone private/protected members (within other rules), this already works in the runtime package and source generator should match the behavior. When #42 lands, use [FastClonerVisibility(FastClonerMemberVisibility.PublicOrInternal)] on your types to match the behavior you wanted.

[lofcz]

released v3.5.4 with the described pattern.