fix(plugin-vue): deprecate inline main (fix #31)

[aweikalee]

Description

vite-plugin-vue should deprecate inline main, because .vue file can't be processed as js/ts.

fix: #31, vite#13756

Additional context

When using vite dev, lang="js" or lang="ts" will be skip build,

Live demo: stackblitz

lang="js" or lang="ts" will as inline main, skip js/ts build. Because its extname is .vue.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the Commit Convention.
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[alamhubb]

#444 I am also trying to solve this problem. Why has this PR not been accepted for so long?

[edison1105]

Closing as #31 has been fixed via #444

[aweikalee]

关闭#31 的问题已通过#444修复

The problem is not completely solved.

#444 only fixed lang="ts", the problem still exists with lang="js".

[sxzz]

@edison1105 We should have an option to disable inline main. Some Vite plugin only transforms .ts files but not Vue files.

[aweikalee]

I think inline main should be deprecated or default to false.
Inline main makes compilation lose consistency.
The same code will compile to different results in lang="js", lang="ts", lang="jsx/tsx".