Decide whether relative imports should name their file extension #1972

Question

Should Studio's relative imports name their file extension, for example import { x } from './foo.ts'?

A cross-model review of #1969 kept suggesting it, and the adjudicator recorded it as a known gap. Today the repo does the opposite on purpose:

• src has 1,444 relative imports, none with an extension.
• No tsconfig sets allowImportingTsExtensions, so a .ts specifier fails tsc (TS5097).

What adopting it would take

• Turn on allowImportingTsExtensions (which needs noEmit or emitDeclarationOnly; Vite already does the emitting).
• Rewrite every relative import, by codemod.
• Add a lint rule so the two styles don't mix.

What it buys is closer alignment with Node's ESM resolution, which matters only for code run by Node without a bundler. The notes in CLAUDE.local.md about replaying modules under node --experimental-strip-types hit exactly that. Nothing in Studio's shipped build needs it.

Low priority. Close as won't-do if extensionless imports stay the house style.

Review-Deferral: 3784139b4d036a24 severity=nit category=maintainability

Raised by the cross-model review of #1969.

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