Bug: should generate conflict-less name for duplicated generated names

[underfin]

The current implementation assigned symbol name is append ${count} if the symbol is conflicting. But the new name maybe also happen conflict. See blowing example.

Input

// shared.js
const a = 'shared.js'

export { a }

// main.js
import { a as a2 } from './shared'
const a = 'index.js'
const a$1 = 'index.js'

console.log(a, a2, a$1)

Build Output

// shared.js
const a = 'shared.js'


// main.js

const a$1 = 'index.js'
const a$1 = 'index.js'

console.log(a$1, a, a$1)

We should assign a name with the current scope that is not a used name, like esbuild findNameUse https://github.com/evanw/esbuild/blob/main/internal/renamer/renamer.go#L564. We need to collect the all symbols for scope at first, we only collect unresolved symbols at now.