fix(gsd): create empty DB for fresh projects with empty .gsd/ (#2510)

ensureDbOpen() and the auto-start DB lifecycle block both gated DB
creation on the presence of Markdown files (DECISIONS.md, REQUIREMENTS.md,
milestones/). In a brand new project, .gsd/ exists but contains no
Markdown yet, so gsd_decision_save returned db_unavailable and the
agent derailed.

Create an empty DB whenever .gsd/ exists, regardless of Markdown content.
Migration runs only when Markdown files are present.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/resources/extensions/gsd/auto-start.ts

@@ -549,17 +549,17 @@ export async function bootstrapAutoSession(
       const hasDecisions = existsSync(join(gsdDirPath, "DECISIONS.md"));
       const hasRequirements = existsSync(join(gsdDirPath, "REQUIREMENTS.md"));
       const hasMilestones = existsSync(join(gsdDirPath, "milestones"));
-      if (hasDecisions || hasRequirements || hasMilestones) {
-        try {
-          const { openDatabase: openDb } = await import("./gsd-db.js");
+      try {
+        const { openDatabase: openDb } = await import("./gsd-db.js");
+        openDb(gsdDbPath);
+        if (hasDecisions || hasRequirements || hasMilestones) {
           const { migrateFromMarkdown } = await import("./md-importer.js");
-          openDb(gsdDbPath);
           migrateFromMarkdown(s.basePath);
-        } catch (err) {
-          process.stderr.write(
-            `gsd-migrate: auto-migration failed: ${(err as Error).message}\n`,
-          );
         }
+      } catch (err) {
+        process.stderr.write(
+          `gsd-migrate: auto-migration failed: ${(err as Error).message}\n`,
+        );
       }
     }
     if (existsSync(gsdDbPath) && !isDbAvailable()) {

src/resources/extensions/gsd/bootstrap/dynamic-tools.ts

@@ -67,6 +67,9 @@ export async function ensureDbOpen(): Promise<boolean> {
         }
         return opened;
       }
+
+      // .gsd/ exists but has no Markdown content (fresh project) — create empty DB
+      return db.openDatabase(dbPath);
     }
 
     return false;

src/resources/extensions/gsd/tests/ensure-db-open.test.ts

@@ -136,9 +136,10 @@ describe('ensure-db-open', () => {
   // ensureDbOpen returns false for empty .gsd/ (no Markdown, no DB)
   // ═══════════════════════════════════════════════════════════════════════════
 
-  test('ensureDbOpen: empty .gsd/ returns false', async () => {
+  test('ensureDbOpen: empty .gsd/ creates empty DB (#2510)', async () => {
     const tmpDir = makeTmpDir();
-    fs.mkdirSync(path.join(tmpDir, '.gsd'), { recursive: true });
+    const gsdDir = path.join(tmpDir, '.gsd');
+    fs.mkdirSync(gsdDir, { recursive: true });
     // .gsd/ exists but no DECISIONS.md, REQUIREMENTS.md, or milestones/
 
     try { closeDatabase(); } catch { /* ok */ }
@@ -148,9 +149,12 @@ describe('ensure-db-open', () => {
     try {
       const { ensureDbOpen } = await import('../bootstrap/dynamic-tools.ts');
       const result = await ensureDbOpen();
-      assert.ok(result === false, 'ensureDbOpen should return false for empty .gsd/');
+      assert.ok(result === true, 'ensureDbOpen should create empty DB for fresh .gsd/');
+      assert.ok(fs.existsSync(path.join(gsdDir, 'gsd.db')), 'DB file should be created');
+      assert.ok(isDbAvailable(), 'DB should be available');
     } finally {
       process.cwd = origCwd;
+      closeDatabase();
       cleanupDir(tmpDir);
     }
   });