feat(eslint): add initial no-default-export-components rule

[JoshuaKGoldberg]

Adds a @sentry/no-default-export-components rule that reports on export defaults of things that seem to be React components.

It intentionally ignores any file where:

• Another module import('...')s the file, which might indicate using a lazy import of a .default
• Existing named imports exist in the file, which I left out to not deal with naming mismatches/conflicts in fixing

Most of the corresponding fixes were in #110263, which this PR was stacked on. A few more violations were added to master since that PR was generated and are now fixed in this PR. This PR also adds detection for class components and fixes those new violations.

There are still ~1.2k export default \w+s in static/app excluding mocks. Collecting more of them will mean adding in more logic to the fixers / lint rule / prompts, which I'd like to propose as a followup.

Fixes ENG-7006.

[github-actions]

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[linear-code]

ENG-7006 Create initial lint rule against default-exported React components

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Class component detection misses MemberExpression superclass patterns

Low Severity

The ClassDeclaration branch only checks node.superClass.type === AST_NODE_TYPES.Identifier, so classes using extends React.Component or extends React.PureComponent (which produce a MemberExpression node, not an Identifier) won't be detected as components. The .name.includes('Component') check also matches non-component classes whose superclass name happens to contain "Component" as a substring, which is overly broad in one direction while missing the MemberExpression pattern entirely.

 

[JoshuaKGoldberg]

We don't do that here, this is fine.