Multiple printers, printer/slot in Spoolman, kept in sync

- One worker per printer (name, IP, CC2 Control URL, own pinned host key);
  a spool sits in at most one slot of one printer, moves between printers
- Spoolman: location "<printer> Slot N" plus extra fields "drucker"/"slot"
  (created by the bridge), cleared and "Lager" on removal
- Full comparison every minute: the printer wins over manual edits of loaded
  spools; stale printer locations go to storage; own locations untouched
- Automatic migration of v1 settings, state and host key
- Status hint when a tag is still in a tray but unmapped (e.g. after
  "Take out" in CC2 Control)
- SSH test: connection drops during exec give a clean error, not a 500
- Mock environment with several printers; tests for all of the above

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014GcEk5tkfFSYD6NTF66NkC

app/spoolman.py

@@ -2,11 +2,21 @@
 
 from __future__ import annotations
 
+import json
 import re
 
 import httpx
 
 
+# Extra fields the bridge keeps on loaded spools (Spoolman stores values JSON-encoded).
+FIELD_PRINTER = "drucker"
+FIELD_SLOT = "slot"
+FIELD_DEFS = {
+    FIELD_PRINTER: {"name": "Drucker", "field_type": "text", "order": 100},
+    FIELD_SLOT: {"name": "Slot", "field_type": "integer", "order": 101},
+}
+
+
 class SpoolmanError(RuntimeError):
     pass
 
@@ -42,8 +52,14 @@ class Spoolman:
     def spools(self, archived: bool = False) -> list[dict]:
         return self._request("GET", "/spool", params={"allow_archived": str(archived).lower()})
 
-    def set_location(self, spool_id: int, location: str) -> dict:
-        return self._request("PATCH", f"/spool/{int(spool_id)}", json={"location": location})
+    def update_spool(self, spool_id: int, body: dict) -> dict:
+        return self._request("PATCH", f"/spool/{int(spool_id)}", json=body)
+
+    def fields(self) -> list[dict]:
+        return self._request("GET", "/field/spool")
+
+    def add_field(self, key: str, params: dict) -> list[dict]:
+        return self._request("POST", f"/field/spool/{key}", json=params)
 
     def use(self, spool_id: int, grams: float) -> dict:
         return self._request("PUT", f"/spool/{int(spool_id)}/use", json={"use_weight": round(float(grams), 3)})
@@ -73,6 +89,16 @@ def color_hex(spool: dict) -> str | None:
     return color if re.fullmatch(r"[0-9A-F]{6}", color) else None
 
 
+def extra_value(spool: dict, key: str):
+    raw = (spool.get("extra") or {}).get(key)
+    if raw is None:
+        return None
+    try:
+        return json.loads(raw)
+    except (TypeError, ValueError):
+        return None
+
+
 def summary(spool: dict) -> dict:
     fil = spool.get("filament") or {}
     return {
@@ -91,4 +117,6 @@ def summary(spool: dict) -> dict:
         "location": spool.get("location") or "",
         "archived": bool(spool.get("archived")),
         "used_weight": spool.get("used_weight"),
+        "printer": extra_value(spool, FIELD_PRINTER),
+        "slot": extra_value(spool, FIELD_SLOT),
     }