Add context-only mode: Claude Code writes blocks, no API needed

New architecture: MCP provides context, Claude Code writes.

New functions:
- get_block_context(case_id, block_id) → returns full context package
  (prompt, source docs, claims, direction, precedents, style guide)
  WITHOUT calling Anthropic API
- save_block_content(case_id, block_id, content) → saves block to DB

New MCP tools: get_block_context, save_block_content

The old write_block (API-based) still works as fallback.
The new flow uses Claude Code's own model (Opus 4.6, 1M context)
which has no separate API billing.

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

mcp-server/src/legal_mcp/tools/drafting.py

@@ -382,6 +382,50 @@ async def export_docx(case_number: str, output_path: str = "") -> str:
         }, ensure_ascii=False, indent=2)
 
 
+async def get_block_context(case_number: str, block_id: str, instructions: str = "") -> str:
+    """קבלת הקשר מלא לכתיבת בלוק — ללא קריאה ל-API. Claude Code כותב את הבלוק.
+
+    Args:
+        case_number: מספר תיק הערר
+        block_id: מזהה הבלוק (block-he, block-vav, ..., block-yod-bet)
+        instructions: הנחיות נוספות
+    """
+    from legal_mcp.services import block_writer
+
+    case = await db.get_case_by_number(case_number)
+    if not case:
+        return f"תיק {case_number} לא נמצא."
+
+    case_id = UUID(case["id"])
+    try:
+        ctx = await block_writer.get_block_context(case_id, block_id, instructions)
+        return json.dumps(ctx, default=str, ensure_ascii=False, indent=2)
+    except ValueError as e:
+        return str(e)
+
+
+async def save_block_content(case_number: str, block_id: str, content: str) -> str:
+    """שמירת בלוק שנכתב ע"י Claude Code ב-DB.
+
+    Args:
+        case_number: מספר תיק הערר
+        block_id: מזהה הבלוק
+        content: הטקסט שנכתב
+    """
+    from legal_mcp.services import block_writer
+
+    case = await db.get_case_by_number(case_number)
+    if not case:
+        return f"תיק {case_number} לא נמצא."
+
+    case_id = UUID(case["id"])
+    try:
+        result = await block_writer.save_block_content(case_id, block_id, content)
+        return json.dumps(result, default=str, ensure_ascii=False, indent=2)
+    except ValueError as e:
+        return str(e)
+
+
 async def analyze_style() -> str:
     """הרצת ניתוח סגנון על קורפוס ההחלטות של דפנה. מחלץ דפוסי כתיבה ושומר אותם."""
     from legal_mcp.services.style_analyzer import analyze_corpus