Strip excluded cargo targets in sdist

[messense]

Closes #2955

[Copilot]

Pull request overview

This PR fixes issue #2955 where maturin fails to strip excluded cargo build targets from source distributions, causing build failures. Since Cargo 1.80, Cargo consistently strips excluded build targets, but maturin was not doing this, resulting in Cargo.toml files referencing source files that don't exist in the sdist.

Changes:

• Implements automatic stripping of cargo targets (lib, bin, example, test, bench) whose source files are excluded from the sdist
• Adds comprehensive test coverage for the new functionality with both included and excluded examples and benchmarks

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/source_distribution.rs	Adds rewrite_cargo_toml_targets function to strip targets with excluded source files; integrates this into sdist generation workflow
src/module_writer/virtual_writer.rs	Changes visibility of exclude method to pub(crate) to support exclusion checks during file filtering
tests/run.rs	Updates test expectations to verify that excluded targets are stripped from Cargo.toml while included targets are retained
test-crates/hello-world/Cargo.toml	Adds test bench and example target declarations for testing the stripping functionality
test-crates/hello-world/pyproject.toml	Configures maturin to exclude specific bench and example files
test-crates/hello-world/benches/*.rs	Adds test benchmark files (both included and excluded variants)
test-crates/hello-world/examples/*.rs	Adds test example files (both included and excluded variants)
test-crates/pyo3-mixed-workspace/.gitignore	Adds standard Rust target/ directory to gitignore
test-crates/pyo3-mixed-src/.gitignore	Adds standard Rust target/ directory to gitignore

[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated no new comments.