Add new Svelte 5 adapter & playground with Typescript included

[jamesst20]

May 16: For those interested, have a look into my fork in the meantime:
https://www.npmjs.com/~jamesstp20
https://www.npmjs.com/package/@jamesst20/inertia-svelte5
https://github.com/jamesst20/inertia
https://github.com/jamesst20/inertia/tree/svelte5-adapter-playground

Original

• Include my Svelte 5 upgrade Upgrade inertia to svelte 5 #1870 +
• Heavily inspired TS upgrade Add Svelte TypeScript support #1866 without any extra changes other than adding types
• All the changes are in a new Svelte5 adapter so no existing code is edited
• I was forced to switch to pnpm (yarn would work too) because otherwise it's impossible to build the adapter. Deleting svelte4 adapter and playground resolve the error and allows to build the v5 so it's likely that NPM is not scoping packages properly. Here is the error:

> svelte-kit sync && svelte-package && publint

> Unexpected character '@'
    at error (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:14256:16)
    at Parser.error (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:14404:3)
    at Parser.acorn_error (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:14391:8)
    at read_expression (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:9641:10)
    at mustache (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:13965:22)
    at new Parser (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:14352:12)
    at parse (/Users/james/Projects/inertia-perso/node_modules/svelte/compiler.cjs:14529:17)
    at parseHtmlx (/Users/james/Projects/inertia-perso/node_modules/svelte2tsx/index.js:1559:22)
    at processSvelteTemplate (/Users/james/Projects/inertia-perso/node_modules/svelte2tsx/index.js:6497:32)
    at svelte2tsx (/Users/james/Projects/inertia-perso/node_modules/svelte2tsx/index.js:6714:178)

• PS: With pnpm I could refer from the playground to the adapter like this which is pretty useful "@inertiajs/svelte5": "workspace:*"
• Edit: Required many attempts but I successfully got the build green!

[jamesst20]

As stated here #1870

Inertia doesn't want a new Svelte adapter nor want to upgrade to Svelte 5 new syntax, runes, etc.

Closing

Edit: May 12 2024: Latest version of this branch is here:
https://github.com/jamesst20/inertia/tree/svelte5-adapter-playground