docs: sync API docs from website

[linfangw]

Mirrors website-owned REST API, Cookbook, and OpenAPI docs after qveris-website release/test changed. Source run: https://github.com/WonderfulValley/qveris-website/actions/runs/26236637463.

[gemini-code-assist]

Code Review

This pull request updates the OpenAPI documentation by adding three new query parameters—query, sort_by, and sort_order—and updating several source line references. The review feedback suggests enhancing these new parameters by adding descriptions and examples to improve documentation quality, and specifically recommends restricting sort_order to an enumeration of 'asc' and 'desc' for better validation.

[gemini-code-assist]

The new query parameters (query, sort_by, sort_order) lack descriptions and examples, which reduces the quality of the public API documentation. Additionally, sort_order should include an enum to restrict values to asc and desc. Providing these details ensures consistency with other well-documented endpoints in this schema and improves the developer experience for API consumers.

          {
            "name": "query",
            "in": "query",
            "required": false,
            "schema": {
              "anyOf": [
                {
                  "type": "string"
                },
                {
                  "type": "null"
                }
              ],
              "title": "Query",
              "description": "Search query to filter providers by name or description."
            },
            "description": "Search query to filter providers by name or description.",
            "example": "cloud"
          },
          {
            "name": "sort_by",
            "in": "query",
            "required": false,
            "schema": {
              "anyOf": [
                {
                  "type": "string"
                },
                {
                  "type": "null"
                }
              ],
              "title": "Sort By",
              "description": "Field to sort the results by (e.g., name, score)."
            },
            "description": "Field to sort the results by (e.g., name, score).",
            "example": "name"
          },
          {
            "name": "sort_order",
            "in": "query",
            "required": false,
            "schema": {
              "type": "string",
              "enum": [
                "asc",
                "desc"
              ],
              "default": "asc",
              "title": "Sort Order",
              "description": "Sort order for the results (asc or desc)."
            },
            "description": "Sort order for the results (asc or desc).",
            "example": "asc"
          }