feat(api)!: use bon to derive builder methods on core structs

[Copilot]

• Add bon crate dependency to Cargo.toml
• Add #[derive(Builder)] to visualizer::Visualizer
• Add #[derive(Builder)] to fs_tree_builder::FsTreeBuilder
• Add #[derive(Builder)] to tree_builder::TreeBuilder
• Add #[derive(Builder)] to app::sub::Sub
• Update doc examples to use builder API
• Update tests/_utils.rs to use FsTreeBuilder::builder()
• Update tests/tree_builder.rs to use TreeBuilder::builder()
• Update tests/visualizer.rs to use Visualizer::builder() in the test macro
• Update tests/json.rs to use FsTreeBuilder::builder() and Visualizer::builder()
• Update tests/cli_errors.rs to use FsTreeBuilder::builder() and Visualizer::builder()
• Update tests/usual_cli.rs to use FsTreeBuilder::builder() and Visualizer::builder() (18 occurrences each)
• Apply master branch updates (USAGE.md, src/usage_md.rs, cli/usage_md.rs, sync tests, updated exports)
• Verify all tests pass

Original prompt

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This section details on the original issue you should resolve

<issue_title>feat(api)!: use bon to convert some structs into a builder function</issue_title>
<issue_description>* [ ] app::sub::Sub

• tree_builder::TreeBuilder
• fs_tree_builder::FsTreeBuilder
• visualizer::Visualizer</issue_description>

<agent_instructions>The repository: https://github.com/elastio/bon

The documentation: https://docs.rs/bon/latest/bon/

The crate page: https://crates.io/crates/bon

Use env DOC=true ./test.sh to run all tests, including documentation.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes feat(api)!: use bon to convert some structs into a builder function #299

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[KSXGitHub]

@copilot Does the test files also make use of these structs? If they do, I would like you to update them as well.

[github-actions]

Performance Regression Reports

commit: c32d5e3

There are no regressions.

[Copilot]

@copilot Does the test files also make use of these structs? If they do, I would like you to update them as well.

Yes, the test files did use these structs. Updated all usages in commit 3cc45c5:

• tests/_utils.rs — FsTreeBuilder
• tests/tree_builder.rs — TreeBuilder
• tests/visualizer.rs — Visualizer (inside the test_case! macro)
• tests/json.rs — FsTreeBuilder and Visualizer
• tests/cli_errors.rs — FsTreeBuilder and Visualizer
• tests/usual_cli.rs — FsTreeBuilder and Visualizer (18 occurrences each)

[KSXGitHub]

@copilot The master branch has just been updated.

[KSXGitHub]

Wrong idea.