[ FEATURE REQUEST ] TypeScript could fix broken "const" variable declaration in JavaScript

In all programming languages, "const" means "a design time constant" which is immutable. But not for JavaScript, it is a variable that is a readonly within context. It is a "readonly" - not a constant.

Type script should easily "fix" this allowing us to use "readonly" for variable declaration.

Wrong:

```
(a: number) => {
const b: number = a || 1; // this is not a constant, this is readonly variable
}

Good:

(a: number) => {
readonly b: number = a || 1; // this makes sense
}
```

And transpiler should be able to easily just rename from "readonly b" to "const b" in JavaScript version of the code.

I as a developer with knowledge of other programming languages have so much issue with abuse of "const" keyword in JavaScript => and TypeScript, yet again has an opportunity to fix broken language.

Pretty please?

Thank you!

No files, tests, or entry points are mentioned. Start by determining whether this TypeScript syntax proposal belongs in this book repository or the TypeScript compiler, then review how TypeScript parses readonly declarations and emits const. Done would require an accepted design and matching parser, type-checker, and transpiler behavior.

Written by the indexing model from the issue text.