feat: implement skeleton phase

src/beaver_gateway/settings.py

@@ -0,0 +1,31 @@
+"""Process-wide configuration loaded from environment (`.env`).
+
+Everything that varies between deployments (creds, paths, ports) lives here.
+User-facing agent/MCP/frontend definitions live in ``/config/config.py``
+and are loaded by ``config_loader`` (Phase 0.3).
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+
+class Settings(BaseSettings):
+    """Runtime environment for the gateway process."""
+
+    model_config = SettingsConfigDict(
+        env_file=".env", env_file_encoding="utf-8", extra="ignore"
+    )
+
+    database_url: str
+    admin_user: str
+    admin_pass: str
+    session_secret: str
+
+    internal_mcp_port: int = 8765
+    config_path: Path = Path("/config/config.py")
+
+    raycast_bearer: str | None = None
+    raycast_config_path: Path = Path("/config/raycast.json")