chore(rebrand): rename WatchStack -> Quivio

Quivio (Kofferwort aus Quire + Video) ersetzt den Arbeitstitel WatchStack.
Es ist origineller, frei auf PyPI/npm, und passt perfekt zur Doppelnatur
der App: Buecher (Quire) + Serien (Video).

Geaendert:
- Python-Paket app/ -> quivio/ (+ alle Imports angepasst)
- DB-File watchstack.db -> quivio.db
- Docker-Image: quivio:0.5.1-beta, Container-Name quivio
- Compose-Services: quivio, quivio-local
- ENV-Vars: QUIVIO_VERSION, QUIVIO_PORT, Volume quivio-data
- Frontend-Logo "W" -> "Q", Titel "Quivio", Footer
- Favicon "Q" (Georgia serif fuer klassischen Look)
- Logger-Name: watchstack -> quivio
- README, NOTICE, dist/README, data/README: Quivio
- CI-Workflow: testet quivio/ Pfade
- build-and-push.sh: lokaler Tag "quivio:VERSION"
- service-Feld in /api/health: quivio
- OpenAPI title: Quivio

Bugfix (gefunden beim Renaming):
- seed.py hatte versteckten "from app.database import DB_PATH" — gefixt

Verifiziert end-to-end:
- Python-Import OK
- Backend: service=quivio, version=0.5.1-beta, 8 unique items
- Docker-Build OK, Push in Gitea-Registry OK (neuer sha256-Digest)
- Container: Quivio 0.5.1-beta ready (logger), HTML ohne WatchStack-Rest
- OpenAPI title=Quivio
- 8 unique items nach cold start (Race-Fix haelt)

quivio/schemas.py

@@ -0,0 +1,155 @@
+"""Pydantic-Schemas für API-Ein- und -Ausgabe."""
+# SPDX-License-Identifier: Apache-2.0
+from __future__ import annotations
+
+from datetime import date, datetime
+from typing import List, Literal, Optional
+
+from pydantic import BaseModel, ConfigDict, Field
+
+
+# ---------- Typen ------------------------------------------------------------
+
+MediaKind = Literal["book", "series"]
+MediaStatus = Literal["plan", "reading", "done", "hold", "dropped"]
+
+
+# ---------- Eingaben ---------------------------------------------------------
+
+class MediaBase(BaseModel):
+    kind: MediaKind
+    title: str = Field(..., max_length=200, min_length=1)
+    original_title: Optional[str] = Field(None, max_length=200)
+    description: Optional[str] = None
+    cover_url: Optional[str] = Field(None, max_length=600)
+    release_year: Optional[int] = Field(None, ge=1800, le=2200)
+    status: MediaStatus = "plan"
+    rating: Optional[float] = Field(None, ge=0, le=10)
+    notes: Optional[str] = None
+
+    # Buch-Felder
+    author: Optional[str] = Field(None, max_length=200)
+    isbn: Optional[str] = Field(None, max_length=20)
+    total_volumes: Optional[int] = Field(None, ge=0)
+    total_chapters: Optional[int] = Field(None, ge=0)
+    total_pages: Optional[int] = Field(None, ge=0)
+    volumes_read: Optional[int] = Field(None, ge=0)
+    chapters_read: Optional[int] = Field(None, ge=0)
+    pages_read: Optional[int] = Field(None, ge=0)
+
+    # Serien-Felder
+    network: Optional[str] = Field(None, max_length=120)
+    total_seasons: Optional[int] = Field(None, ge=0)
+    total_episodes: Optional[int] = Field(None, ge=0)
+    episodes_watched: Optional[int] = Field(None, ge=0)
+    season_watching: Optional[int] = Field(None, ge=0)
+    start_date: Optional[date] = None
+    end_date: Optional[date] = None
+
+    genres: List[str] = []
+    tags: List[str] = []
+
+
+class MediaCreate(MediaBase):
+    pass
+
+
+class MediaUpdate(BaseModel):
+    """Alle Felder optional – PATCH-Semantik."""
+    title: Optional[str] = Field(None, max_length=200, min_length=1)
+    original_title: Optional[str] = None
+    description: Optional[str] = None
+    cover_url: Optional[str] = None
+    release_year: Optional[int] = None
+    status: Optional[MediaStatus] = None
+    rating: Optional[float] = Field(None, ge=0, le=10)
+    notes: Optional[str] = None
+    author: Optional[str] = None
+    isbn: Optional[str] = None
+    total_volumes: Optional[int] = None
+    total_chapters: Optional[int] = None
+    total_pages: Optional[int] = None
+    volumes_read: Optional[int] = None
+    chapters_read: Optional[int] = None
+    pages_read: Optional[int] = None
+    network: Optional[str] = None
+    total_seasons: Optional[int] = None
+    total_episodes: Optional[int] = None
+    episodes_watched: Optional[int] = None
+    season_watching: Optional[int] = None
+    start_date: Optional[date] = None
+    end_date: Optional[date] = None
+    genres: Optional[List[str]] = None
+    tags: Optional[List[str]] = None
+
+
+class ProgressUpdate(BaseModel):
+    """Schnelles Fortschritts-Update."""
+    delta: int = 1
+    set_to: Optional[int] = None  # wenn angegeben, setzt absolut
+
+
+# ---------- Ausgaben ---------------------------------------------------------
+
+class GenreOut(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+    id: int
+    name: str
+
+
+class TagOut(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+    id: int
+    name: str
+
+
+class MediaOut(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+    id: int
+    kind: str
+    title: str
+    original_title: Optional[str]
+    description: Optional[str]
+    cover_url: Optional[str]
+    release_year: Optional[int]
+    status: str
+    rating: Optional[float]
+    notes: Optional[str]
+    author: Optional[str]
+    isbn: Optional[str]
+    total_volumes: Optional[int]
+    total_chapters: Optional[int]
+    total_pages: Optional[int]
+    volumes_read: Optional[int]
+    chapters_read: Optional[int]
+    pages_read: Optional[int]
+    network: Optional[str]
+    total_seasons: Optional[int]
+    total_episodes: Optional[int]
+    episodes_watched: Optional[int]
+    season_watching: Optional[int]
+    start_date: Optional[date]
+    end_date: Optional[date]
+    progress_percent: float
+    genres: List[GenreOut]
+    tags: List[TagOut]
+    created_at: datetime
+    updated_at: datetime
+
+
+class StatsBucket(BaseModel):
+    status: str
+    count: int
+
+
+class StatsPerKind(BaseModel):
+    kind: str
+    total: int
+    avg_rating: Optional[float]
+    by_status: List[StatsBucket]
+
+
+class StatsResponse(BaseModel):
+    books: StatsPerKind
+    series: StatsPerKind
+    total_entries: int