backend: Pydantic response_models für 5 GET-Endpoints hinzufügen

- health.py: HealthResponse
- eigenleben.py: EigenlebenOverviewResponse + SkillTextResponse
- chronik.py: ChronikResponse + ChronikItem
- wissen.py: WissenListResponse + WissenFileResponse
- reminders.py: ReminderListResponse + ReminderOut

py_compile bestanden, /docs zeigt neue Schemata.
Response-Payloads unverändert — nur Typisierung hinzugefügt.

backend/routers/reminders.py

@@ -2,9 +2,10 @@
 Konsument ist v.a. der Hermes-Agent via mcp_mc.py (reminder_create/list/delete);
 LAN-only wie alle MC2-Endpoints."""
 
-from fastapi import APIRouter, HTTPException
 from pydantic import BaseModel
 
+from fastapi import APIRouter, HTTPException
+
 from services import reminders
 
 router = APIRouter(prefix="/api")
@@ -16,7 +17,20 @@ class ReminderIn(BaseModel):
     repeat: str = ""   # '' einmalig | daily | weekdays | weekly
 
 
-@router.get("/reminders")
+class ReminderOut(BaseModel):
+    id: int
+    text: str
+    next_ts: float
+    repeat: str
+    created_ts: float
+    when_local: str
+
+
+class ReminderListResponse(BaseModel):
+    items: list[ReminderOut]
+
+
+@router.get("/reminders", response_model=ReminderListResponse)
 def list_reminders() -> dict:
     return {"items": reminders.list_all()}