fix(ssr): load sourcemaps alongside modules (fix: #3288)

[Vap0r1ze]

Description

Fixes #3288

This PR adds runtime sourcemaps to SSR modules inline.
This isn't a very large change as vite's request transformer provides source maps. The only modification that needed to be made to the source maps was prepending ';;;' to the mappings, as the first three lines of every module will look like this:

async function(a, b, c
) {
'use strict';

Before Changes

After Changes

---

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

[Vap0r1ze]

It may be worth noting that this also allows me to use breakpoints in VSCode without any debugger; statements

[Vap0r1ze]

Video of me setting a breakpoint in a TS file in an Astro project with my changes and saving the file (to cause the module to be reloaded)

Code_NCoKzatZOR.mp4

[jere2101]

Just tested it with SvelteKit and it works great (EDIT: for me ;D)🎉
Thank for the fast implementation

[patak-dev]

@manucorporat would you review this one in the context of Qwik?

[jere2101]

Don't know if it helps.

In my test with Qwik debugging worked perfectly fine🤩 but I'm not an Qwik expert.

[Vap0r1ze]

@patak-dev is there anything blocking this pr, testing?

[sapphi-red]

Thanks for the PR!
The behavior looks good to me.

[pasqui23]

@jere2101 what was the launch.json you used to debug SvelteKit's SSR?

[jere2101]

@jere2101 what was the launch.json you used to debug SvelteKit's SSR?

I tested it without a launch.json. I started npm run dev in the Javascript Debug Terminal of vscode.
Hope this help's you

[Vap0r1ze]

@sapphi-red I think I've addressed your concerns now

[sapphi-red]

LGTM 👍

[benmccann]

This PR seems to have broken source maps for SvelteKit as SvelteKit's test suite is now failing:

I think we should probably revert this PR and add it back only with tests ensuring the source map locations it generates are correct.