Add semver-checks workflow

[dkgoutham]

Adds a new GitHub Actions workflow that uses cargo-semver-checks to automatically detect versioning violations in Rust crates. This helps prevent accidental breaking changes and ensures proper version bumping according to semver rules.

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
mycrate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[dkgoutham]

I have a few questions:

1. Should I add the workspace-level semver configuration to Cargo.toml? Like currently, the template has workspace lints for clippy/rust, should semver-checks configuration follow the same pattern?
2. Should we configure specific semver lint behaviors for the template? For example, do we want #[must_use] additions to be warnings instead of errors?
3. Should we make it easy for template users to disable this workflow if they don't want it?

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
mycrate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
mycrate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
mycrate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
template_crate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
template_crate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[svlachakis]

The way the semver-check workflow works:

Scenario 1: New Project

• No version tags exist
• Workflow runs but skips semver check
• Prints helpful message about creating first tag

Scenario 2: Existing Project

• Has tag v0.1.0
• You modify Cargo.toml and create PR
• Workflow compares current code against v1.0.0
• Fails if you removed a public function (breaking change)
• Passes if you only added new features (non-breaking)

Scenario 3: Release

• You push tag v0.1.1
• Workflow runs and compares v0.1.1 against v0.1.0
• Validates that the version bump matches the changes

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
template_crate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[github-actions]

Coverage after merging add-semver-checks into main will be

64.71%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
template_crate/src
lib.rs	66.67%	100%	80%	64.71%	33–44

[maksimryndin]

Awesome work @svlachakis and @dkgoutham ! 👍 thanks a lot! Let's introduce small changes and merge

[github-actions]

Coverage after merging add-semver-checks into main will be

64.29%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
template_crate/src
lib.rs	66.67%	100%	80%	64.29%	33–36, 38–40, 42–44

[maksimryndin]

LGTM! 👍