fix(core/version): enforce minimum wire-compatible version

Clamp wire-facing client version to 0.98.0 for User-Agent and /models client_version when local builds report older versions like 0.0.0.

Adds regression tests for UA and remote model query behavior.

Fixes #539

code-rs/code-version/src/lib.rs

@@ -8,7 +8,68 @@ pub const CODE_VERSION: &str = {
     }
 };
 
+pub const MIN_WIRE_COMPAT_VERSION: &str = "0.98.0";
+
+fn parse_semver_triplet(version: &str) -> Option<(u64, u64, u64)> {
+    let core = version.split_once(['-', '+']).map_or(version, |(v, _)| v);
+    let mut parts = core.split('.');
+
+    let major = parts.next()?.parse().ok()?;
+    let minor = parts.next()?.parse().ok()?;
+    let patch = parts.next()?.parse().ok()?;
+
+    Some((major, minor, patch))
+}
+
+fn wire_compatible_version_for(version: &str) -> &str {
+    let Some(version_triplet) = parse_semver_triplet(version) else {
+        return version;
+    };
+    let Some(min_triplet) = parse_semver_triplet(MIN_WIRE_COMPAT_VERSION) else {
+        return version;
+    };
+
+    if version_triplet < min_triplet {
+        MIN_WIRE_COMPAT_VERSION
+    } else {
+        version
+    }
+}
+
 #[inline]
 pub fn version() -> &'static str {
     CODE_VERSION
 }
+
+#[inline]
+pub fn wire_compatible_version() -> &'static str {
+    wire_compatible_version_for(CODE_VERSION)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn wire_compat_clamps_old_versions() {
+        assert_eq!(wire_compatible_version_for("0.0.0"), MIN_WIRE_COMPAT_VERSION);
+        assert_eq!(wire_compatible_version_for("0.6.59"), MIN_WIRE_COMPAT_VERSION);
+        assert_eq!(
+            wire_compatible_version_for("0.6.59-dev+abc123"),
+            MIN_WIRE_COMPAT_VERSION
+        );
+    }
+
+    #[test]
+    fn wire_compat_keeps_new_versions() {
+        assert_eq!(wire_compatible_version_for("0.98.0"), "0.98.0");
+        assert_eq!(wire_compatible_version_for("0.99.1"), "0.99.1");
+        assert_eq!(wire_compatible_version_for("1.0.0"), "1.0.0");
+    }
+
+    #[test]
+    fn wire_compat_keeps_invalid_versions() {
+        assert_eq!(wire_compatible_version_for("dev"), "dev");
+        assert_eq!(wire_compatible_version_for("0.1"), "0.1");
+    }
+}