enhance WFS search functionality to include relevance scores

[esgn]

closes #28

Summary

This PR updates gpf_wfs_search_types to propagate relevance scores returned by @ignfab/gpf-schema-store.

The tool now returns an optional score field for each search result when the catalog provides it. When no score is available, the field is omitted from the response.

Changes

• bump @ignfab/gpf-schema-store from 0.1.2 to 0.1.3
• update WfsClient to use the scored catalog search API
• remove the old unscored searchFeatureTypes() helper in favor of searchFeatureTypesWithScores()
• extend gpf_wfs_search_types output schema with an optional score
• keep the response clean by omitting score when it is undefined
• update the README to document that gpf_wfs_search_types can return relevance scores
• add and update tests for:
  • scored search results in the WFS client
  • score propagation in the MCP tool response
  • omission of score when the catalog does not provide one

Example

Before:

{
  "results": [
    {
      "id": "BDTOPO_V3:batiment",
      "title": "Batiment",
      "description": "..."
    }
  ]
}

After:

{
  "results": [
    {
      "id": "BDTOPO_V3:batiment",
      "title": "Batiment",
      "description": "...",
      "score": 12.5
    }
  ]
}

If no score is returned by the catalog, the score field is not included.

Validation

• npm test -- --runTestsByPath test/gpf/wfs.test.ts
• npm test -- --runTestsByPath test/tools/wfs.test.ts