feat: add gws version bare subcommand (#71)

* feat: add `gws version` bare subcommand

* refactor: extract help and version flag checks into dedicated functions and add test coverage guidance to AGENTS.md

---------

Co-authored-by: jpoehnelt-bot <jpoehnelt-bot@users.noreply.github.com>

.changeset/version-subcommand.md

@@ -0,0 +1,5 @@
+---
+"@googleworkspace/cli": patch
+---
+
+Add `gws version` as a bare subcommand alongside `gws --version` and `gws -V`

AGENTS.md

@@ -12,6 +12,9 @@
 
 ## Build & Test
 
+> [!IMPORTANT]
+> **Test Coverage**: The `codecov/patch` check requires that new or modified lines are covered by tests. When adding code, extract testable helper functions rather than embedding logic in `main`/`run` where it's hard to unit-test. Run `cargo test` locally and verify new branches are exercised.
+
 ```bash
 cargo build          # Build in dev mode
 cargo clippy -- -D warnings  # Lint check

src/main.rs

@@ -68,12 +68,12 @@ async fn run() -> Result<(), GwsError> {
     let first_arg = &args[1];
 
     // Handle --help and --version at top level
-    if first_arg == "--help" || first_arg == "-h" {
+    if is_help_flag(first_arg) {
         print_usage();
         return Ok(());
     }
 
-    if first_arg == "--version" || first_arg == "-V" {
+    if is_version_flag(first_arg) {
         println!("gws {}", env!("CARGO_PKG_VERSION"));
         return Ok(());
     }
@@ -399,6 +399,14 @@ fn print_usage() {
     println!("    Please search existing issues first; if one already exists, comment there.");
 }
 
+fn is_help_flag(arg: &str) -> bool {
+    matches!(arg, "--help" | "-h")
+}
+
+fn is_version_flag(arg: &str) -> bool {
+    matches!(arg, "--version" | "-V" | "version")
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -480,6 +488,24 @@ mod tests {
         assert_eq!(config.mode, helpers::modelarmor::SanitizeMode::Block);
     }
 
+    #[test]
+    fn test_is_version_flag() {
+        assert!(is_version_flag("--version"));
+        assert!(is_version_flag("-V"));
+        assert!(is_version_flag("version"));
+        assert!(!is_version_flag("--ver"));
+        assert!(!is_version_flag("v"));
+        assert!(!is_version_flag("drive"));
+    }
+
+    #[test]
+    fn test_is_help_flag() {
+        assert!(is_help_flag("--help"));
+        assert!(is_help_flag("-h"));
+        assert!(!is_help_flag("help"));
+        assert!(!is_help_flag("--h"));
+    }
+
     #[test]
     fn test_resolve_method_from_matches_basic() {
         let mut resources = std::collections::HashMap::new();