Add JSON Schema for import_rules.yaml

[Copilot]

This introduces a machine-readable schema for import_rules rules files so they can be validated/autocompleted by YAML-aware tooling and submitted to SchemaStore.

• Schema definition (import_rules.schema.json)
  • Added a Draft-07 JSON Schema at repo root.
  • Encodes top-level config:
    • rules (required)
    • severity (error | warning | info)
  • Encodes per-rule structure:
    • required: reason, target, disallow
    • optional: exclude_target, exclude_disallow, severity
  • Supports string | string[] forms for target/disallow fields.
  • Restricts unknown fields via additionalProperties: false (top-level and per rule).

This PR now contains only import_rules.schema.json.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Add a YAML schema</issue_title>
<issue_description>Add a YAML schema for rules files and register it to SchemaStore.org.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Add a YAML schema #19

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[fujidaiti]

@copilot Revert all changes except import_rules.schema.json

[Copilot]

@copilot Revert all changes except import_rules.schema.json

Done in 3cf21c8. I reverted all previously added changes except import_rules.schema.json, so the PR now only keeps that schema file.

[fujidaiti]

TODO

• add schema tests using https://pub.dev/packages/json_schema