Add alias for absolute imports in coral.

[programmiri]

About this change - What it does
Configures TS and vite to use absolut imports where "@/" maps to coral/src.
Adds a eslint rule to restrict imports using relative paths except from the same directory.

Why this way
Avoiding relative imports is making potential refactoring more smooth. It also adds readability for the imports.

[SmuliS]

What do you feel about changing @ into ´src´. That way we would not have a magic alias, but something that follows the directory structure.

[SmuliS]

How do you feel about changing "@/*" -> "src/*". So basically we would not introduce any real aliases, but we would always start the absolute imports from src.

[SmuliS]

We could also approach the problem differently without the use of aliases. We could do the following change to tsconfig.json:

"baseUrl": ".",
"paths": {
  "@/*": ["src/*"]
},

->

"baseUrl": "src",

and in vite.config.ts we could replace the alias:

resolve: {
  alias: {
    "@": resolve(rootPath, "./src"),
  },
},

with a root definition: root: resolve(__dirname, "src").

That way the src would be the true root directory and we could import eveything as import App from "App";. If we would implement the followin approach, we would also need to move index.html to src directory, but I think that OK as that file can be considered as source code and not a static asset.

[programmiri]

What do you feel about changing @ into ´src´. That way we would not have a magic alias, but something that follows the directory structure.

We can do that! I like the magic @ because than it's e.g. @/domain/... and @/components which adds readability, but src instead of @ is not really a big difference, so pure personal preference 😬 Will change that!

[programmiri]

We could also approach the problem differently without the use of aliases. We could do the following change to tsconfig.json:

"baseUrl": ".",
"paths": {
  "@/*": ["src/*"]
},

->

"baseUrl": "src",

and in vite.config.ts we could replace the alias:

resolve: {
  alias: {
    "@": resolve(rootPath, "./src"),
  },
},

with a root definition: root: resolve(__dirname, "src").

That way the src would be the true root directory and we could import eveything as import App from "App";. If we would implement the followin approach, we would also need to move index.html to src directory, but I think that OK as that file can be considered as source code and not a static asset.

I'll try if that works (without too much config in vite)!

[SmuliS]

Two very minor comments. Looks like it works without setting the root in vite.config.ts.