Simplify changes rule drops breaking changes when the same type also has simple changes

[AdriVanHoudt]

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Describe the bug

When a diff of a type has both a breaking change and simple change, the simplify rules silently drops the breaking change.

To Reproduce Steps to reproduce the behaviour:

// packages/core/__tests__/diff/rules/simplify-changes.test.ts

  test('keeps a breaking field type change when the same field also gains a description', async () => {
    const a = buildSchema(/* GraphQL */ `
      type Payload {
        id: String!
      }
      type Query {
        _: Boolean
      }
      type Mutation {
        doSomething(id: String!): Payload!
      }
    `);
    const b = buildSchema(/* GraphQL */ `
      type Payload {
        id: String!
      }
      type Query {
        _: Boolean
      }
      type Mutation {
        "Does something."
        doSomething(id: String!): Boolean!
      }
    `);

    const changes = await diff(a, b, [simplifyChanges]);

    // The breaking type change must survive simplification even though the same field also gained a description in the same diff. 
    // `simplifyChanges` treats `FieldDescriptionAdded` as a "simple change" and pushes its path, the later `FieldTypeChanged` shares that exact path and is wrongly filtered out.
    const typeChange = changes.find(c => c.type === ChangeType.FieldTypeChanged);
    expect(typeChange).toBeDefined();
    expect(typeChange?.criticality.level).toBe(CriticalityLevel.Breaking);
  });

Expected behavior

Check should never drop breaking changes.

Environment:

• OS: macos 26
• @graphql-inspector/...: @graphql-hive/cli@0.59.2 which resolves @graphql-inspector/core@7.1.3
• graphql: 16
• NodeJS: 22

Additional context

I can PR the failing test and willing to implement a fix but would need some guidance on where to best fix this.