[fix] Fix rvalue error when using arrow functions in {@const}

[baseballyama]

fix: #7206

In addition to #7206, I added support for various more edge cases.
I have tried to cover as much as possible, but please let me know if there are any omissions.

I noticed that the process of {@const} is similar to {#if}. I looked for a way to completely reuse the processing of {if}, but I couldn't implement it.
If you have any ideas on how to do this, I would appreciate your comments.

Before submitting the PR, please make sure you do the following

• It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs
• Prefix your PR title with [feat], [fix], [chore], or [docs].
• This message body should clearly illustrate what problems it solves.
• Ideally, include a test that fails without this PR but passes with it.

Tests

• Run the tests with npm test and lint the project with npm run lint

[baseballyama]

There is multiple issues that will be fixed by this PR. can someone review this?

#7423
#7431
#7206

[tanhauhau]

sorry hijacking your PR, i've modified the implementation to fix #7221 too