Incorporate art-dag-mono repo into artdag/ subfolder

Merges full history from art-dag/mono.git into the monorepo
under the artdag/ directory. Contains: core (DAG engine),
l1 (Celery rendering server), l2 (ActivityPub registry),
common (shared templates/middleware), client (CLI), test (e2e).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

git-subtree-dir: artdag
git-subtree-mainline: 1a179de547
git-subtree-split: 4c2e716558

artdag/l2/app/config.py

@@ -0,0 +1,67 @@
+"""
+L2 Server Configuration.
+
+Environment-based settings for the ActivityPub server.
+"""
+
+import os
+from dataclasses import dataclass
+from pathlib import Path
+
+
+@dataclass
+class Settings:
+    """L2 Server configuration."""
+
+    # Domain and URLs
+    domain: str = os.environ.get("ARTDAG_DOMAIN", "artdag.rose-ash.com")
+    l1_public_url: str = os.environ.get("L1_PUBLIC_URL", "https://celery-artdag.rose-ash.com")
+    effects_repo_url: str = os.environ.get("EFFECTS_REPO_URL", "https://git.rose-ash.com/art-dag/effects")
+    ipfs_gateway_url: str = os.environ.get("IPFS_GATEWAY_URL", "")
+
+    # L1 servers
+    l1_servers: list = None
+
+    # Cookie domain for cross-subdomain auth
+    cookie_domain: str = None
+
+    # Data directory
+    data_dir: Path = None
+
+    # JWT settings
+    jwt_secret: str = os.environ.get("JWT_SECRET", "")
+    jwt_algorithm: str = "HS256"
+    access_token_expire_minutes: int = 60 * 24 * 30  # 30 days
+
+    # OAuth SSO (via account.rose-ash.com)
+    oauth_authorize_url: str = os.environ.get("OAUTH_AUTHORIZE_URL", "https://account.rose-ash.com/auth/oauth/authorize")
+    oauth_token_url: str = os.environ.get("OAUTH_TOKEN_URL", "https://account.rose-ash.com/auth/oauth/token")
+    oauth_client_id: str = os.environ.get("OAUTH_CLIENT_ID", "artdag_l2")
+    oauth_redirect_uri: str = os.environ.get("OAUTH_REDIRECT_URI", "https://artdag.rose-ash.com/auth/callback")
+    oauth_logout_url: str = os.environ.get("OAUTH_LOGOUT_URL", "https://account.rose-ash.com/auth/sso-logout/")
+    secret_key: str = os.environ.get("SECRET_KEY", "change-me-in-production")
+
+    # Internal account URL for server-to-server token exchange (avoids external DNS/TLS)
+    internal_account_url: str = os.environ.get("INTERNAL_URL_ACCOUNT", "")
+
+    def __post_init__(self):
+        # Parse L1 servers
+        l1_str = os.environ.get("L1_SERVERS", "https://celery-artdag.rose-ash.com")
+        self.l1_servers = [s.strip() for s in l1_str.split(",") if s.strip()]
+
+        # Cookie domain
+        env_cookie = os.environ.get("COOKIE_DOMAIN")
+        if env_cookie:
+            self.cookie_domain = env_cookie
+        else:
+            parts = self.domain.split(".")
+            if len(parts) >= 2:
+                self.cookie_domain = "." + ".".join(parts[-2:])
+
+        # Data directory
+        self.data_dir = Path(os.environ.get("ARTDAG_DATA", str(Path.home() / ".artdag" / "l2")))
+        self.data_dir.mkdir(parents=True, exist_ok=True)
+        (self.data_dir / "assets").mkdir(exist_ok=True)
+
+
+settings = Settings()