Snapshots: Liste ohne Volltext, Lazy-Load + serverseitige Suche

Backend:
- GET /{id}/snapshots liefert nur noch schlanke Shape (Metadaten +
  SUBSTR(summary,1,300) AS summary_preview), kein Volltext, kein sources_json.
- Neuer Endpunkt GET /{id}/snapshots/{snapshot_id} fuer Volltext-Lazy-Load.
- Neuer Endpunkt GET /{id}/snapshots/search?q=... fuer serverseitige
  Volltextsuche ueber alle Snapshots einer Lage.

Frontend:
- api.js: getSnapshot() und searchSnapshots() ergaenzt.
- app.js: _snapshotFullCache, Volltext wird beim Aufklappen eines
  Snapshot-Eintrags per lazyLoadSnapshotDetail() nachgeladen und gecacht.
- Suche ueber Snapshots filtert weiterhin clientseitig ueber summary_preview.

Hintergrund: Bei grossen Lagen (Iran-Lage: 347 Snapshots) fiel die
Snapshots-Listenantwort mit Volltext-Summaries auf ~54 MB. Die Liste
faellt damit auf ~150 KB; Volltexte werden nur on-demand geladen.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/routers/incidents.py

@@ -337,12 +337,17 @@ async def get_snapshots(
     current_user: dict = Depends(get_current_user),
     db: aiosqlite.Connection = Depends(db_dependency),
 ):
-    """Lageberichte (Snapshots) einer Lage abrufen."""
+    """Lageberichte (Snapshots) einer Lage abrufen — schlanke Liste.
+
+    Liefert nur Metadaten und einen 300-Zeichen-Preview des Summary.
+    Der Volltext (summary + sources_json) wird per Einzel-Endpunkt
+    ``GET /{incident_id}/snapshots/{snapshot_id}`` bei Bedarf geladen.
+    """
     tenant_id = current_user.get("tenant_id")
     await _check_incident_access(db, incident_id, current_user["id"], tenant_id)
     cursor = await db.execute(
-        """SELECT id, incident_id, summary, sources_json,
-                  article_count, fact_check_count, created_at
+        """SELECT id, incident_id, article_count, fact_check_count, created_at,
+                  SUBSTR(summary, 1, 300) AS summary_preview
            FROM incident_snapshots WHERE incident_id = ?
            ORDER BY created_at DESC""",
         (incident_id,),
@@ -351,6 +356,55 @@ async def get_snapshots(
     return [dict(row) for row in rows]
 
 
+@router.get("/{incident_id}/snapshots/search")
+async def search_snapshots(
+    incident_id: int,
+    q: str = Query(..., min_length=2, max_length=200),
+    current_user: dict = Depends(get_current_user),
+    db: aiosqlite.Connection = Depends(db_dependency),
+):
+    """Volltextsuche über alle Snapshots einer Lage.
+
+    Liefert dieselbe schlanke Shape wie der Listen-Endpunkt,
+    gefiltert per ``summary LIKE '%q%'``.
+    """
+    tenant_id = current_user.get("tenant_id")
+    await _check_incident_access(db, incident_id, current_user["id"], tenant_id)
+    like = f"%{q}%"
+    cursor = await db.execute(
+        """SELECT id, incident_id, article_count, fact_check_count, created_at,
+                  SUBSTR(summary, 1, 300) AS summary_preview
+           FROM incident_snapshots
+           WHERE incident_id = ? AND summary LIKE ?
+           ORDER BY created_at DESC""",
+        (incident_id, like),
+    )
+    rows = await cursor.fetchall()
+    return [dict(row) for row in rows]
+
+
+@router.get("/{incident_id}/snapshots/{snapshot_id}")
+async def get_snapshot(
+    incident_id: int,
+    snapshot_id: int,
+    current_user: dict = Depends(get_current_user),
+    db: aiosqlite.Connection = Depends(db_dependency),
+):
+    """Einzelnen Snapshot mit vollem Summary + sources_json abrufen (Lazy-Load)."""
+    tenant_id = current_user.get("tenant_id")
+    await _check_incident_access(db, incident_id, current_user["id"], tenant_id)
+    cursor = await db.execute(
+        """SELECT id, incident_id, summary, sources_json,
+                  article_count, fact_check_count, created_at
+           FROM incident_snapshots WHERE id = ? AND incident_id = ?""",
+        (snapshot_id, incident_id),
+    )
+    row = await cursor.fetchone()
+    if not row:
+        raise HTTPException(status_code=404, detail="Snapshot nicht gefunden")
+    return dict(row)
+
+
 @router.get("/{incident_id}/factchecks")
 async def get_factchecks(
     incident_id: int,