feat(integrations): add Grok Build skills-based integration (#3535)

* feat(integrations): add Grok Build skills-based integration

Add first-class support for xAI Grok Build via SkillsIntegration, installing
speckit skills under .grok/skills and wiring init/invocation/catalog surfaces.

Assisted-by: Grok Build (model: grok-4, supervised)

* test+docs: address Copilot review on Grok multi-install and next steps

Assert init next-steps guidance for Grok (.grok/skills, /speckit-*) and
clarify that multi-install safety is path/manifest isolation, not
agent-context defaults such as shared AGENTS.md.

* fix(integrations): Grok headless --always-approve and isolation paths

Document Grok multi-install isolation as .grok/skills and .grok/rules.
Override build_exec_args to pass --always-approve so non-interactive
dispatch is not blocked at tool permission gates.

* docs(integrations): list only managed .grok/skills for Grok isolation

Multi-install isolation documents Spec Kit-managed paths; Grok only
writes .grok/skills, so drop the read-only .grok/rules entry.

* fix(integrations): always-slash Grok hooks and refresh catalog date

Move grok to ALWAYS_SLASH_AGENTS so hooks never emit /speckit.plan when
ai_skills is missing/false. Update slash-format tests, persist ai_skills
on init, and bump catalog updated_at for the Grok entry.

---------

Co-authored-by: Nate Chadwick <1232206+natechadwick@users.noreply.github.com>
Co-authored-by: test <test@example.com>

src/specify_cli/integrations/__init__.py

@@ -63,6 +63,7 @@ def _register_builtins() -> None:
     from .gemini import GeminiIntegration
     from .generic import GenericIntegration
     from .goose import GooseIntegration
+    from .grok import GrokIntegration
     from .hermes import HermesIntegration
     from .junie import JunieIntegration
     from .kilocode import KilocodeIntegration
@@ -99,6 +100,7 @@ def _register_builtins() -> None:
     _register(GeminiIntegration())
     _register(GenericIntegration())
     _register(GooseIntegration())
+    _register(GrokIntegration())
     _register(HermesIntegration())
     _register(JunieIntegration())
     _register(KilocodeIntegration())

src/specify_cli/integrations/grok/__init__.py

@@ -0,0 +1,60 @@
+"""Grok Build integration — skills-based agent.
+
+Grok Build discovers project skills from ``.grok/skills/speckit-<name>/SKILL.md``
+(and also scans ``.agents/skills/``). Spec Kit installs into the native
+``.grok/skills`` tree so skills take highest local priority.
+"""
+
+from __future__ import annotations
+
+from ..base import SkillsIntegration
+
+
+class GrokIntegration(SkillsIntegration):
+    """Integration for xAI Grok Build CLI."""
+
+    key = "grok"
+    config = {
+        "name": "Grok Build",
+        "folder": ".grok/",
+        "commands_subdir": "skills",
+        "install_url": "https://docs.x.ai/build/overview",
+        "requires_cli": True,
+    }
+    registrar_config = {
+        "dir": ".grok/skills",
+        "format": "markdown",
+        "args": "$ARGUMENTS",
+        "extension": "/SKILL.md",
+    }
+    multi_install_safe = True
+
+    def build_exec_args(
+        self,
+        prompt: str,
+        *,
+        model: str | None = None,
+        output_json: bool = True,
+    ) -> list[str] | None:
+        """Build CLI arguments for non-interactive ``grok`` execution.
+
+        Mandatory headless flag:
+
+        * ``--always-approve`` — auto-approve tool executions so workflow
+          dispatch and ``dispatch_command()`` are not blocked at permission
+          gates (same role as Cursor's ``--force`` / Copilot's ``--yolo``).
+        """
+        if not self.config or not self.config.get("requires_cli"):
+            return None
+        args = [
+            self._resolve_executable(),
+            "-p",
+            prompt,
+            "--always-approve",
+        ]
+        self._apply_extra_args_env_var(args)
+        if model:
+            args.extend(["--model", model])
+        if output_json:
+            args.extend(["--output-format", "json"])
+        return args