Add: Decisive appraiser (שמאי מכריע) search via gov.il public API

Adds a new MCP tool `search_decisive_appraisals` that queries the
Ministry of Justice public registry (~30K published decisions) by
block (גוש), plot (חלקה), appraiser name, committee, decision/publicity
date ranges, or free text — and returns metadata + direct PDF URLs.

Implementation notes:
- New `nadlan_mcp/govil/` package, parallel to `nadlan_mcp/govmap/`,
  for gov.il APIs that are not Govmap. Pydantic v2 models match the
  upstream PascalCase response via aliases.
- Upstream sits behind an F5 WAF that rejects standard `requests`;
  uses `curl_cffi` with Chrome 120 impersonation to traverse it.
- Static `x-client-id` header (issued to the gov.il SPA, public, visible
  in any DevTools session) is required by the gateway — without it
  every call returns a generic 500.
- 14 unit tests cover model parsing, body shape, pagination, and the
  500-is-fatal contract (configuration error, not retryable).

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

pyproject.toml

@@ -27,6 +27,7 @@ dependencies = [
     "python-dotenv>=1.0.0",
     "pydantic>=2.0.0",
     "fastmcp>=2.13.0,<3.0.0",
+    "curl_cffi>=0.5.0",
 ]
 
 [project.optional-dependencies]