fix(build): match only semver tags in git_version()

Change --match pattern from "v*" to "v[0-9]*" so that
git describe only considers semantic version tags (e.g. v0.0.28)
and skips non-version tags like vm-dev.

Closes #832

Author: Ai-chan-0411

crates/openshell-core/build.rs

@@ -64,7 +64,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 /// Returns `None` when git is unavailable or the repo has no matching tags.
 fn git_version() -> Option<String> {
     let output = std::process::Command::new("git")
-        .args(["describe", "--tags", "--long", "--match", "v*"])
+        .args(["describe", "--tags", "--long", "--match", "v[0-9]*"])
         .output()
         .ok()?;