Backend Sprint 2+3: Health-Modul, Multi-Dog Tagebuch, Pillow, Migrations

- database.py: diary_dogs + walk_participant_dogs Tabellen, idempotente
  Migration für Health-Felder (charge_nr, kosten, diagnose, …), Backfill
- routes/health.py: vollständiges Health-Modul (war Stub), CRUD für
  Impfung/Entwurmung/Tierarzt/Medikament/Gewicht/Allergie/Dokument
- routes/diary.py: Multi-Dog n:m via diary_dogs (dog_ids in allen Endpoints)
- routes/dogs.py: Foto-Upload konvertiert HEIC/PNG/WebP → JPEG via Pillow
- routes/poison.py: Resolve mit Grundauswahl + Soft-Delete (geloest_von/at/grund)
- ki.py: health_summary() für KI-Gesundheitsbericht
- main.py: /favicon.ico Route
- requirements.txt: Pillow 11.2.1 + pillow-heif 0.22.0

backend/database.py

@@ -88,6 +88,14 @@ def init_db():
         );
         CREATE INDEX IF NOT EXISTS idx_diary_dog ON diary(dog_id, datum DESC);
 
+        -- TAGEBUCH ↔ HUNDE (n:m — ein Eintrag kann mehrere Hunde betreffen)
+        CREATE TABLE IF NOT EXISTS diary_dogs (
+            diary_id INTEGER NOT NULL REFERENCES diary(id) ON DELETE CASCADE,
+            dog_id   INTEGER NOT NULL REFERENCES dogs(id) ON DELETE CASCADE,
+            PRIMARY KEY (diary_id, dog_id)
+        );
+        CREATE INDEX IF NOT EXISTS idx_diary_dogs_dog ON diary_dogs(dog_id);
+
         -- GESUNDHEIT
         CREATE TABLE IF NOT EXISTS health (
             id           INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -186,6 +194,15 @@ def init_db():
             PRIMARY KEY (walk_id, user_id)
         );
 
+        -- GASSI-TREFFEN ↔ HUNDE (n:m — Teilnehmer kann mehrere Hunde mitbringen)
+        CREATE TABLE IF NOT EXISTS walk_participant_dogs (
+            walk_id  INTEGER NOT NULL REFERENCES walks(id)  ON DELETE CASCADE,
+            user_id  INTEGER NOT NULL REFERENCES users(id)  ON DELETE CASCADE,
+            dog_id   INTEGER NOT NULL REFERENCES dogs(id)   ON DELETE CASCADE,
+            PRIMARY KEY (walk_id, user_id, dog_id)
+        );
+        CREATE INDEX IF NOT EXISTS idx_wpd_dog ON walk_participant_dogs(dog_id);
+
         -- FORUM
         CREATE TABLE IF NOT EXISTS forum_threads (
             id          INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -234,4 +251,48 @@ def init_db():
 
         """)
 
+    # Migrations: neue Spalten zu bestehenden Tabellen hinzufügen (idempotent)
+    _migrate(conn_factory=db)
+
     logger.info("Datenbank initialisiert.")
+
+
+def _migrate(conn_factory):
+    """Fügt fehlende Spalten hinzu und führt Datenmigration durch (idempotent)."""
+    migrations = [
+        # Giftköder: Auflösungs-Details für spätere KI-Analyse
+        ("poison", "geloest_von",   "INTEGER"),
+        ("poison", "geloest_at",    "TEXT"),
+        ("poison", "geloest_grund", "TEXT"),
+        # Gesundheit: erweiterte Felder je nach Eintragstyp
+        ("health", "charge_nr",     "TEXT"),
+        ("health", "tierarzt_name", "TEXT"),
+        ("health", "kosten",        "REAL"),
+        ("health", "diagnose",      "TEXT"),
+        ("health", "dosierung",     "TEXT"),
+        ("health", "haeufigkeit",   "TEXT"),
+        ("health", "aktiv",         "INTEGER NOT NULL DEFAULT 1"),
+        ("health", "bis_datum",     "TEXT"),
+        ("health", "schweregrad",   "TEXT"),
+        ("health", "reaktion",      "TEXT"),
+        ("health", "datei_url",     "TEXT"),
+        ("health", "datei_typ",     "TEXT"),
+    ]
+    with conn_factory() as conn:
+        for table, column, col_type in migrations:
+            existing = [
+                row[1] for row in
+                conn.execute(f"PRAGMA table_info({table})").fetchall()
+            ]
+            if column not in existing:
+                conn.execute(
+                    f"ALTER TABLE {table} ADD COLUMN {column} {col_type}"
+                )
+                logger.info(f"Migration: {table}.{column} hinzugefügt.")
+
+        # Datenmigration: diary_dogs für bestehende Einträge befüllen
+        conn.execute("""
+            INSERT OR IGNORE INTO diary_dogs (diary_id, dog_id)
+            SELECT id, dog_id FROM diary
+        """)
+        logger.info("Migration: diary_dogs Backfill abgeschlossen.")