feat(version): add build metadata fields

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/lib/versionInfo.ts

@@ -5,5 +5,7 @@ export interface VersionInfo {
   commitHash: string | null;
   commitDate: string | null;
   commitSubject: string | null;
+  lastUpdated: string | null;
+  commitMessage: string | null;
   buildTime: string | null;
 }

src/scripts/generateVersionInfo.ts

@@ -72,6 +72,8 @@ function main(): void {
     commitHash,
     commitDate,
     commitSubject,
+    lastUpdated: commitDate ?? buildTime,
+    commitMessage: commitSubject,
     buildTime,
   };
 
@@ -89,4 +91,4 @@ function main(): void {
   console.log(`[version-info] wrote src/generated/versionInfo.json (${label})`);
 }
 
-main();
+main();