fix(server): handle files named HEAD in git status

apps/server/src/vcs/GitVcsDriverCore.test.ts

@@ -950,6 +950,27 @@ it.layer(TestLayer)("GitVcsDriver core integration", (it) => {
       }),
     );
 
+    it.effect("reports changes to a file named HEAD", () =>
+      Effect.gen(function* () {
+        const cwd = yield* makeTmpDir();
+        yield* initRepoWithCommit(cwd);
+        yield* writeTextFile(cwd, "HEAD", "first line\n");
+        yield* git(cwd, ["add", "HEAD"]);
+        yield* git(cwd, ["commit", "-m", "add HEAD file"]);
+        yield* writeTextFile(cwd, "HEAD", "first line\nsecond line\n");
+
+        const status = yield* (yield* GitVcsDriver.GitVcsDriver).statusDetails(cwd);
+
+        assert.equal(status.isRepo, true);
+        assert.equal(status.hasWorkingTreeChanges, true);
+        assert.deepInclude(status.workingTree.files, {
+          path: "HEAD",
+          insertions: 1,
+          deletions: 0,
+        });
+      }),
+    );
+
     it.effect("reports default-branch delta separately from upstream delta", () =>
       Effect.gen(function* () {
         const cwd = yield* makeTmpDir();

apps/server/src/vcs/GitVcsDriverCore.ts

@@ -420,9 +420,10 @@ function isNonRepositoryGitStderr(stderr: string): boolean {
   return stderr.toLowerCase().includes("not a git repository");
 }
 function isUnbornHeadStderr(stderr: string): boolean {
+  const normalized = stderr.toLowerCase();
   return (
-    stderr.toLowerCase().includes("unknown revision") &&
-    stderr.toLowerCase().includes("path not in the working tree")
+    normalized.includes("bad revision 'head'") ||
+    (normalized.includes("unknown revision") && normalized.includes("path not in the working tree"))
   );
 }
 
@@ -1600,7 +1601,7 @@ export const makeGitVcsDriverCore = Effect.fn("makeGitVcsDriverCore")(function*
         executeGitWithStableDiagnostics(
           "GitVcsDriver.statusDetails.numstat",
           cwd,
-          ["diff", "HEAD", "--numstat"],
+          ["diff", "HEAD", "--numstat", "--"],
           { allowNonZeroExit: true },
         ).pipe(
           Effect.flatMap((result) => {
@@ -1642,7 +1643,7 @@ export const makeGitVcsDriverCore = Effect.fn("makeGitVcsDriverCore")(function*
                 ...gitCommandContext({
                   operation: "GitVcsDriver.statusDetails.numstat",
                   cwd,
-                  args: ["diff", "HEAD", "--numstat"],
+                  args: ["diff", "HEAD", "--numstat", "--"],
                 }),
                 detail: "git diff HEAD --numstat failed.",
                 exitCode: result.exitCode,