feat: Add code quality findings support

[Andrei-hub11]

Adds support for the REST Code Quality findings endpoints in go-github.

This includes ListFindings and GetFinding on CodeQualityService, the finding data models, unit tests, generated accessors, a pagination iterator, and manual metadata entries in openapi_operations.yaml so the change stays aligned with the project's documentation and code generation patterns.

Closes: #4327

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[gmlewis]

This file should not be hand-edited, so you will need to revert the changes to this file.

I'm on my phone now, but tomorrow I can update this file in a separate PR which you can then pull into this PR so we can move forward with it.

[Andrei-hub11]

Ok

[Andrei-hub11]

I got confused because one of the CI scripts seems to require this. Maybe I missed something.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.48%. Comparing base (595de3d) to head (681fa0f).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4330   +/-   ##
=======================================
  Coverage   97.48%   97.48%           
=======================================
  Files         193      193           
  Lines       19400    19440   +40     
=======================================
+ Hits        18912    18952   +40     
  Misses        270      270           
  Partials      218      218           

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[alexandear]

Must match the schema:

{
  "type": "array",
  "items": {
    "description": "Code quality finding",
    "type": "object",
    "properties": {
      "number": {
        "description": "The finding number.",
        "type": "integer"
      },
      "state": {
        "description": "State of the code quality finding.",
        "type": "string",
        "enum": [
          "open",
          "dismissed"
        ]
      },
      "url": {
        "description": "The REST API URL of the code quality finding resource.",
        "type": "string",
        "format": "uri"
      },
      "rule": {
        "description": "Code quality rule",
        "type": "object",
        "properties": {
          "id": {
            "description": "A unique identifier for the rule used to detect the finding.",
            "type": "string"
          },
          "title": {
            "description": "The name of the rule used to detect the finding.",
            "type": "string"
          },
          "description": {
            "description": "A short description of the rule used to detect the finding.",
            "type": "string"
          },
          "help": {
            "description": "A detailed description of the rule used to detect the finding.",
            "type": "string"
          },
          "severity": {
            "description": "The severity of the rule used to detect the finding.",
            "type": "string",
            "enum": [
              "error",
              "warning",
              "note",
              "none"
            ]
          },
          "category": {
            "description": "The category of the rule used to detect the finding.",
            "type": "string",
            "enum": [
              "none",
              "maintainability",
              "reliability"
            ]
          }
        },
        "required": [
          "id",
          "title",
          "description",
          "severity",
          "category"
        ]
      },
      "location": {
        "description": "Code quality file location",
        "type": "object",
        "properties": {
          "path": {
            "description": "The file path where the finding was detected.",
            "type": "string"
          },
          "start_line": {
            "description": "The line number where the finding starts.",
            "type": "integer"
          },
          "start_column": {
            "description": "The column number where the finding starts.",
            "type": "integer"
          },
          "end_line": {
            "description": "The line number where the finding ends.",
            "type": "integer"
          },
          "end_column": {
            "description": "The column number where the finding ends.",
            "type": "integer"
          }
        },
        "required": [
          "path"
        ]
      },
      "message": {
        "description": "Code quality finding message",
        "type": "object",
        "properties": {
          "text": {
            "description": "The message text of the code quality finding.",
            "type": "string"
          },
          "markdown": {
            "description": "The message text of the code quality finding in markdown format.",
            "type": "string"
          }
        },
        "required": [
          "text",
          "markdown"
        ]
      },
      "created_at": {
        "description": "The time the code quality finding was created.",
        "type": "string",
        "format": "date-time"
      }
    },
    "required": [
      "number",
      "state",
      "url",
      "rule",
      "location",
      "message"
    ]
  }
}