🐛 Typescripts "Module" syntax is invalid for typescript-enabled common js

[JacobLey]

Environment information

CLI:
  Version:                      1.6.1
  Color support:                true

Platform:
  CPU Architecture:             aarch64
  OS:                           linux

Environment:
  BIOME_LOG_DIR:                unset
  NO_COLOR:                     unset
  TERM:                         "xterm-256color"
  JS_RUNTIME_VERSION:           "v20.11.1"
  JS_RUNTIME_NAME:              "node"
  NODE_PACKAGE_MANAGER:         unset

Biome Configuration:
  Status:                       Loaded successfully
  Formatter disabled:           false
  Linter disabled:              true
  Organize imports disabled:    false
  VCS disabled:                 false

Workspace:
  Open Documents:               0

What happened?

1. Create a file called index.cts (this is a forced commonjs file, but it is typescript so we are allowed to used use ESM-like syntax: https://www.typescriptlang.org/play?module=1#code/KYDwDg9gTgLgBAE2AMwIYFcA28DecDGAVgM4BccMU6wcAvgNxA).
2. Add an export to the file using ESM-like syntax (e.g. export default { cjs: true };)
3. Run biome format .
4. Get parsing error:

./src/tests/data/cjs.cts:1:1 parse ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  × Illegal use of an export declaration outside of a module
  
  > 1 │ export default { cjs: true };
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    2 │ 
  
  i not allowed inside scripts

See playground: https://biomejs.dev/playground/?code=ZQB4AHAAbwByAHQAIABkAGUAZgBhAHUAbAB0ACAAewAgAGMAagBzADoAIAB0AHIAdQBlACAAfQA7AAoA&typescript=false&jsx=false&script=true

Expected result

Biome should recognize that this is a typescript file (.cts not .cjs), and therefore ESM-like syntax is allowed.

Perhaps more generally, maybe it should recognize that some other transpiler will be touching this code before execution, so seemingly invalid code is actually allowed and formatting should proceed as usual.

To be clear, the intention of this error is correct. If I were using import/export in a .cjs file (or a .js file with { "type": "commonjs" }) I would expect this error to occur.

In the Biome playground I needed to set the source type to Script to get the failure, which explicitly disables the ability to enable typescript. I suspect there is some failure to recognize .cts as module+typescript, rather than commonjs.

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