Add document preview, delete, and fix scroll in documents panel

Documents tab was limited to ~9 visible items due to fixed max-height
without overflow-hidden. Now uses 70vh with proper overflow. Added
click-to-preview (shows extracted text in dialog) and delete button
with confirmation dialog + backend DELETE endpoint.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/app.py

@@ -2436,6 +2436,31 @@ async def api_reprocess_document(case_number: str, doc_id: str):
     return {"status": "reprocessing"}
 
 
+@app.delete("/api/cases/{case_number}/documents/{doc_id}")
+async def api_delete_document(case_number: str, doc_id: str):
+    """Delete a single document from a case (including its chunks and file)."""
+    case = await db.get_case_by_number(case_number)
+    if not case:
+        raise HTTPException(404, f"תיק {case_number} לא נמצא")
+
+    case_id = UUID(case["id"])
+    document_id = UUID(doc_id)
+    doc = await db.get_document(document_id)
+    if not doc or UUID(doc["case_id"]) != case_id:
+        raise HTTPException(404, "מסמך לא נמצא בתיק")
+
+    # Try to remove the physical file
+    file_path = doc.get("file_path")
+    if file_path:
+        import pathlib
+        p = pathlib.Path(file_path)
+        if p.exists():
+            p.unlink(missing_ok=True)
+
+    await db.delete_document(document_id)
+    return {"deleted": True, "doc_id": doc_id}
+
+
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