fix: revert tsconfig change, fix types

[dummdidumm]

The inclusion of svelte.config.js is a breaking change since it's type-checked now and that can break projects which did type-check without errors previously
closes #11906

Also relaxes the report-uri types, fully qualified urls are also ok
closes #11905

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[benmccann]

The workaround for this bug is pretty nasty. You can't extend include, which means that a user has to put this in their tsconfig.json:

	"include": [
		"./svelte-kit/ambient.d.ts",
		"./svelte-kit/non-ambient.d.ts",
		"./svelte-kit/types/**/$types.d.ts",
		"svelte.config.js",
		"vite.config.js",
		"vite.config.ts",
		"src/**/*.js",
		"src/**/*.ts",
		"src/**/*.svelte",
		"tests/**/*.js",
		"tests/**/*.ts",
		"tests/**/*.svelte"
	],

I'd be inclined to just fix the CSP types and see if it's still giving folks trouble to include svelte.config.js. While it could be considered a bit of a breaking change to include it, it could also be considered a bug fix as we shouldn't have overlooked it and omitted it in the first place.

[benmccann]

I should mention also that the thing that drove #11886 was trying to upgrade a large project to Svelte 5. The project has a ton of createEventDispatcher usage and it turned into a real mess trying to migrate to component props because TypeScript can't differentiate between functions returning void vs Promise<void>. There are, however, several typescript-eslint rules that help enforce proper usage of promises. However, enabling these rules becomes a lot more difficult if #11886 is reverted and I'm afraid that will make it much more of a headache for people to migrate their projects to Svelte 5. Currently the lint rules will only catch issues in the script block. I filed sveltejs/eslint-plugin-svelte#691 to request catching issues in the markup as well.

[AdrianGonz97]

If the tsconfig change is reverted, perhaps an alternative for now (until the next major version) would be to adjust the create-svelte template to include a // @ts-check at the top of the svelte.config.js file? This change should be OK since it'll only affect new projects.

[benmccann]

While that would help the Svelte config file get type checked, it doesn't seem likely to fix the issue I'm trying to address which is that you can't set recommended-type-checked today because the eslint and tsconfig point to different sets of files

[MathiasWP]

The workaround for this bug is pretty nasty. You can't extend include, which means that a user has to put this in their tsconfig.json:

	"include": [
		"./svelte-kit/ambient.d.ts",
		"./svelte-kit/non-ambient.d.ts",
		"./svelte-kit/types/**/$types.d.ts",
		"svelte.config.js",
		"vite.config.js",
		"vite.config.ts",
		"src/**/*.js",
		"src/**/*.ts",
		"src/**/*.svelte",
		"tests/**/*.js",
		"tests/**/*.ts",
		"tests/**/*.svelte"
	],

I'd be inclined to just fix the CSP types and see if it's still giving folks trouble to include svelte.config.js. While it could be considered a bit of a breaking change to include it, it could also be considered a bug fix as we shouldn't have overlooked it and omitted it in the first place.

IMO fixing the CSP rules is a good compromise. I don't have any problems with the svelte config file being type-checked, i only had problems with incorrect types.

[dummdidumm]

Still strongly in favor of reverting this for 2.0 and looking at it again in 3.0