add Signal command and control bot service

Python service for jeeves that communicates over Signal via signal-cli-rest-api.
Implements device verification via safety numbers (unverified devices cannot
run commands until verified over SSH), and a van inventory command that uses
an LLM on BOB (ollama) to parse receipt photos or text lists into structured
inventory data. The LLM backend is configurable to swap models easily.

https://claude.ai/code/session_01AKXQBuVBsW7J1YbukDiQ7A

python/signal_bot/signal_client.py

@@ -0,0 +1,112 @@
+"""Client for the signal-cli-rest-api."""
+
+from __future__ import annotations
+
+import logging
+from typing import Any
+
+import httpx
+
+from python.signal_bot.models import SignalMessage
+
+logger = logging.getLogger(__name__)
+
+
+class SignalClient:
+    """Communicate with signal-cli-rest-api.
+
+    Args:
+        base_url: URL of the signal-cli-rest-api (e.g. http://localhost:8989).
+        phone_number: The registered phone number to send/receive as.
+    """
+
+    def __init__(self, base_url: str, phone_number: str) -> None:
+        self.base_url = base_url.rstrip("/")
+        self.phone_number = phone_number
+        self._client = httpx.Client(base_url=self.base_url, timeout=30)
+
+    def receive(self) -> list[SignalMessage]:
+        """Poll for new messages."""
+        response = self._client.get(f"/v1/receive/{self.phone_number}")
+        response.raise_for_status()
+        envelopes: list[dict[str, Any]] = response.json()
+
+        messages: list[SignalMessage] = []
+        for raw in envelopes:
+            envelope = raw.get("envelope", {})
+            data_message = envelope.get("dataMessage")
+            if not data_message:
+                continue
+
+            attachment_ids = [
+                att["id"] for att in data_message.get("attachments", []) if "id" in att
+            ]
+
+            group_info = data_message.get("groupInfo")
+            group_id = group_info.get("groupId") if group_info else None
+
+            messages.append(
+                SignalMessage(
+                    source=envelope.get("source", ""),
+                    timestamp=envelope.get("timestamp", 0),
+                    message=data_message.get("message", "") or "",
+                    attachments=attachment_ids,
+                    group_id=group_id,
+                ),
+            )
+
+        return messages
+
+    def send(self, recipient: str, message: str) -> None:
+        """Send a text message."""
+        payload = {
+            "message": message,
+            "number": self.phone_number,
+            "recipients": [recipient],
+        }
+        response = self._client.post("/v2/send", json=payload)
+        response.raise_for_status()
+
+    def send_to_group(self, group_id: str, message: str) -> None:
+        """Send a message to a group."""
+        payload = {
+            "message": message,
+            "number": self.phone_number,
+            "recipients": [group_id],
+        }
+        response = self._client.post("/v2/send", json=payload)
+        response.raise_for_status()
+
+    def get_attachment(self, attachment_id: str) -> bytes:
+        """Download an attachment by ID."""
+        response = self._client.get(f"/v1/attachments/{attachment_id}")
+        response.raise_for_status()
+        return response.content
+
+    def get_identities(self) -> list[dict[str, Any]]:
+        """List known identities and their trust levels."""
+        response = self._client.get(f"/v1/identities/{self.phone_number}")
+        response.raise_for_status()
+        return response.json()
+
+    def trust_identity(self, number_to_trust: str, *, trust_all_known_keys: bool = False) -> None:
+        """Trust an identity (verify safety number)."""
+        payload: dict[str, Any] = {}
+        if trust_all_known_keys:
+            payload["trust_all_known_keys"] = True
+        response = self._client.put(
+            f"/v1/identities/{self.phone_number}/trust/{number_to_trust}",
+            json=payload,
+        )
+        response.raise_for_status()
+
+    def reply(self, message: SignalMessage, text: str) -> None:
+        """Reply to a message, routing to group or individual."""
+        if message.group_id:
+            self.send_to_group(message.group_id, text)
+        else:
+            self.send(message.source, text)
+
+    def close(self) -> None:
+        """Close the HTTP client."""
+        self._client.close()