fix(orchestrator): E3 disable builtin Claude.ai MCP connectors via --strict-mcp-config

Smoke run 3 showed agents loading builtin Anthropic connectors
(mcp__claude_ai_Gmail__authenticate, Google Calendar, Notion, Drive)
alongside our 5 roboco MCP servers. The connectors bloat the tool
surface and give the LLM 'discover' targets it shouldn't have.

The Claude Code CLI's --strict-mcp-config flag tells it to load ONLY
the servers from --mcp-config, ignoring all builtin defaults. Added
to _append_image_and_claude_args next to --mcp-config.

Note: the existing --tools allowlist (Read,Write,Edit,Bash,Grep,Glob,
Task,TodoWrite) only filters builtin tools, not MCP-prefixed ones —
that's why the connectors slipped through.

Spec ref: docs/superpowers/specs/2026-05-12-post-smoke-3-fixes-design.md
section E3.

roboco/runtime/orchestrator.py

@@ -1704,6 +1704,7 @@ class AgentOrchestrator:
                 "/app/system-prompt.md",
                 "--mcp-config",
                 "/app/mcp-config.json",
+                "--strict-mcp-config",
                 "--tools",
                 "Read,Write,Edit,Bash,Grep,Glob,Task,TodoWrite",
                 "--output-format",

tests/unit/runtime/test_spawn_strict_mcp.py

@@ -0,0 +1,69 @@
+"""Wave E3: agent spawn cmd uses --strict-mcp-config to suppress builtin
+Anthropic connectors (Gmail / Google Calendar / Notion / Google Drive).
+
+Without --strict-mcp-config, the Claude Code CLI auto-registers its
+builtin MCP connectors alongside our --mcp-config entries — they appear
+in the agent's tool inventory as `mcp__claude_ai_Gmail__authenticate`
+etc. The flag tells the CLI to load ONLY the servers from --mcp-config.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+from unittest.mock import patch
+
+from roboco.models.runtime import OrchestratorAgentConfig, SpawnGitContext
+from roboco.runtime.orchestrator import AgentOrchestrator
+
+_MAX_FLAG_ADJACENCY = 3
+
+
+def _make_dev_config() -> OrchestratorAgentConfig:
+    """Minimal AgentConfig for a developer."""
+    return OrchestratorAgentConfig(
+        agent_id="be-dev-1",
+        blueprint_path=Path("/app/agents/blueprints/be-dev-1.md"),
+        model="sonnet",
+        mcp_config_path=Path("/app/mcp-config.json"),
+        git_context=SpawnGitContext(
+            project_slug="roboco-api",
+            branch_name="feature/backend/TASK0001",
+        ),
+    )
+
+
+def _build_image_args(config: OrchestratorAgentConfig) -> list[str]:
+    """Invoke _append_image_and_claude_args against an empty cmd."""
+    cmd: list[str] = []
+    with patch(
+        "roboco.runtime.orchestrator._resolve_agent_cli_model",
+        return_value="claude-sonnet-4-6",
+    ):
+        AgentOrchestrator._append_image_and_claude_args(cmd, config, None)
+    return cmd
+
+
+class TestSpawnStrictMcpConfig:
+    """Agent spawn cmd includes --strict-mcp-config."""
+
+    def test_cmd_contains_strict_mcp_config_flag(self) -> None:
+        """docker run cmd for an agent includes --strict-mcp-config."""
+        cmd = _build_image_args(_make_dev_config())
+        assert "--strict-mcp-config" in cmd, (
+            f"--strict-mcp-config flag missing from spawn cmd. Without it, "
+            f"the Claude CLI auto-registers builtin connectors (Gmail, "
+            f"Calendar, Notion, Drive) alongside our roboco MCP servers. "
+            f"Full cmd: {cmd}"
+        )
+
+    def test_strict_mcp_config_paired_with_mcp_config(self) -> None:
+        """--strict-mcp-config appears alongside --mcp-config /app/mcp-config.json."""
+        cmd = _build_image_args(_make_dev_config())
+        assert "--mcp-config" in cmd
+        mcp_idx = cmd.index("--mcp-config")
+        assert cmd[mcp_idx + 1] == "/app/mcp-config.json"
+        strict_idx = cmd.index("--strict-mcp-config")
+        assert abs(strict_idx - mcp_idx) <= _MAX_FLAG_ADJACENCY, (
+            f"--strict-mcp-config should appear near --mcp-config; "
+            f"strict_idx={strict_idx}, mcp_idx={mcp_idx}. Cmd: {cmd}"
+        )