feat: add ambiguous export error

[underfin]

Description

Support give a warning for ambiguous export. Here is an example, the warning message is port from rollup.

[NAMESPACE_CONFLICT] Warning: Found ambiguous export.
   ╭─[main.js:1:10]
   │
 1 │ import { value } from "./foo";
   │          ──┬──  
   │            ╰──── "foo.js" re-exports "value" from one of the modules "b.js" and "a.js" (will be ignored).
───╯

Test Plan

Added.

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[underfin]

Warning

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• feat: determine circular dependency #398
• feat: add ambiguous export error #397 👈
• feat: missing export error #396
• main

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