fix: register gsd-workflow-guard.js in settings.json during install (#1772)

The hook was built, copied to hooks/dist/, and installed to disk — but
never registered as a PreToolUse entry in settings.json, making the
hooks.workflow_guard config flag permanently inert.

Adds the registration block following the same pattern as the other
community hooks (prompt-guard, read-guard, validate-commit, etc.).

Includes regression test that verifies every JS hook in gsdHooks has a
corresponding command construction and registration block.

Fixes #1767

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

bin/install.js

@@ -5635,6 +5635,30 @@ function install(isGlobal, runtime = 'claude') {
     // and exits silently (no-op) if not enabled. This lets users enable
     // them per-project by adding: "hooks": { "community": true }
 
+    // Configure workflow guard hook (opt-in via hooks.workflow_guard: true)
+    // Detects file edits outside GSD workflow context and advises using
+    // /gsd-quick or /gsd-fast for state-tracked changes. Advisory only.
+    const workflowGuardCommand = isGlobal
+      ? buildHookCommand(targetDir, 'gsd-workflow-guard.js')
+      : 'node ' + dirName + '/hooks/gsd-workflow-guard.js';
+    const hasWorkflowGuardHook = settings.hooks[preToolEvent].some(entry =>
+      entry.hooks && entry.hooks.some(h => h.command && h.command.includes('gsd-workflow-guard'))
+    );
+
+    if (!hasWorkflowGuardHook) {
+      settings.hooks[preToolEvent].push({
+        matcher: 'Write|Edit',
+        hooks: [
+          {
+            type: 'command',
+            command: workflowGuardCommand,
+            timeout: 5
+          }
+        ]
+      });
+      console.log(`  ${green}✓${reset} Configured workflow guard hook (opt-in via hooks.workflow_guard)`);
+    }
+
     // Configure commit validation hook (Conventional Commits enforcement, opt-in)
     const validateCommitCommand = isGlobal
       ? 'bash ' + targetDir.replace(/\\/g, '/') + '/hooks/gsd-validate-commit.sh'