🐛 lint/suspicious/noRedeclare - Index signatures still conflict with var names.

[lgarron]

Environment information

CLI:
  Version:                      1.1.0
  Color support:                true

Platform:
  CPU Architecture:             aarch64
  OS:                           macos

Environment:
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  NO_COLOR:                     unset
  TERM:                         "xterm-256color"
  JS_RUNTIME_VERSION:           "v20.5.0"
  JS_RUNTIME_NAME:              "node"
  NODE_PACKAGE_MANAGER:         "npm/9.8.0"

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What happened?

Consider the following code:

function process(
  input: { [type: string]: string },
  f: (s: string) => number
): ClipboardItemInterface {
  // biome-ignore lint/style/noVar: Need to use `var` for `esbuild` to target ES5.
  var output_: { [type: string]: number } = {};
  // biome-ignore lint/style/noVar: Need to use `var` for `esbuild` to target ES5.
  for (var type in items) {
    output[type] = f(input[type])
  }
  return output;
}

Due to the use of var, a version of rome/tools#4478 still occurs:

Shouldn't redeclare 'type'. Consider to delete it or rename it. [lint/suspicious/noRedeclare](https://biomejs.dev/lint/rules/noRedeclare)

The issue doesn't appear if the for loop uses const. Hoisting the var out of the loop declaration doesn't help.

As noted in the comments of the snippet, it is necessary to use var for code targeted at ES5 environments. See https://github.com/lgarron/clipboard-polyfill/blob/c24845e280262858cf40c5fce8443abf5a8dc51b/src/clipboard-polyfill/ClipboardItem/ClipboardItemPolyfill.ts#L19 for a real-world use case.

Expected result

No error.

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