feat(batch-agent): extract Batch Agent Service (Step 3)

- agent_runner: local directory + cloud agent orchestration via Redis
- 5 domain agents: filesystem, task, note, project, timeline
- integrations: Gmail, MS Graph (Outlook + Teams)
- journey: guided chatbot conversation to build prompt_template
- routes: REST endpoints (catalog, can-create, trigger)
- redis_consumer: subscribes to batch:request:* pattern
- ws_context: Redis-based execute_on_client for tool round-trip
- Dockerfile with 300s timeout for long-running batch jobs

services/batch-agent/app/integrations/__init__.py

@@ -0,0 +1,108 @@
+"""Cloud provider integration utilities.
+
+Adapted for Batch Agent Service: import from shared.config instead of app.config.
+
+Provides:
+  * Shared message dataclasses (EmailMessage, ChatMessage)
+  * get_provider() — factory for Gmail/MS Graph clients
+  * encrypt_token() / decrypt_token() — Fernet-based OAuth token encryption
+"""
+
+from __future__ import annotations
+
+import json
+import logging
+from dataclasses import dataclass, field
+from datetime import datetime
+from typing import TYPE_CHECKING
+
+from cryptography.fernet import Fernet, InvalidToken
+
+from shared.config import settings
+
+if TYPE_CHECKING:
+    from app.integrations.gmail import GmailClient
+    from app.integrations.ms_graph import MSGraphClient
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class EmailMessage:
+    id: str
+    subject: str
+    sender: str
+    body_text: str
+    date: datetime
+    labels: list[str] = field(default_factory=list)
+
+    @property
+    def as_text(self) -> str:
+        date_str = self.date.strftime("%Y-%m-%d %H:%M")
+        labels_str = f" [{', '.join(self.labels)}]" if self.labels else ""
+        return (
+            f"From: {self.sender}\n"
+            f"Date: {date_str}{labels_str}\n"
+            f"Subject: {self.subject}\n\n"
+            f"{self.body_text}"
+        )
+
+
+@dataclass
+class ChatMessage:
+    id: str
+    content: str
+    sender: str
+    channel: str | None
+    date: datetime
+
+    @property
+    def as_text(self) -> str:
+        date_str = self.date.strftime("%Y-%m-%d %H:%M")
+        channel_str = f" [channel: {self.channel}]" if self.channel else ""
+        return (
+            f"From: {self.sender}\n"
+            f"Date: {date_str}{channel_str}\n\n"
+            f"{self.content}"
+        )
+
+
+def _get_fernet() -> Fernet:
+    key = settings.OAUTH_ENCRYPTION_KEY
+    if not key:
+        raise RuntimeError(
+            "OAUTH_ENCRYPTION_KEY is not set. "
+            "Generate one with: python -c \"from cryptography.fernet import Fernet; print(Fernet.generate_key().decode())\""
+        )
+    return Fernet(key.encode() if isinstance(key, str) else key)
+
+
+def encrypt_token(token_info: dict) -> str:
+    if not isinstance(token_info, dict) or not token_info:
+        raise ValueError("token_info must be a non-empty dict")
+    plaintext = json.dumps(token_info).encode("utf-8")
+    return _get_fernet().encrypt(plaintext).decode("utf-8")
+
+
+def decrypt_token(encrypted: str) -> dict:
+    try:
+        plaintext = _get_fernet().decrypt(encrypted.encode("utf-8"))
+        return json.loads(plaintext)
+    except (InvalidToken, json.JSONDecodeError) as exc:
+        raise ValueError(f"Failed to decrypt OAuth token: {exc}") from exc
+
+
+def get_provider(
+    provider: str,
+    credentials_info: dict,
+) -> "GmailClient | MSGraphClient":
+    if provider == "gmail":
+        from app.integrations.gmail import GmailClient
+        return GmailClient(credentials_info)
+    if provider in {"outlook", "teams"}:
+        from app.integrations.ms_graph import MSGraphClient
+        return MSGraphClient(credentials_info)
+    raise ValueError(
+        f"Unknown cloud provider {provider!r}. "
+        "Supported: 'gmail', 'outlook', 'teams'."
+    )