Improve buggy stdlib bundling on ScalaJS

[jiribenes]

ScalaJS' pickler has some limit on string sizes which the recent stdlib additions changes overshoot by a lot on my computer.
This was preventing me from building the project locally.

The fix is horrible: we just chunk the string instead. Perhaps there's a better fix.

We generate a stdlib-resources.json file which is then loaded by JS, thus removing the !!!MULTILINEMARKER!!! hack and generating huge Scala files altogether. :)

This ought to:

• be tested with the website
• be ported to mill (this is also solvable solved by Revert #1278 (Add build.mill setup) #1387)
• be reconciled with a bundler or something like it to ensure that the json is bundled

---

[info] compiling 111 Scala sources to /nix/var/nix/builds/nix-63932-2468348747/effekt-src/effekt/js/target/scala-3.3.6/classes ...

  unhandled exception while running pickler on /nix/var/nix/builds/nix-63932-2468348747/effekt-src/effekt/js/target/scala-3.3.6/src_managed/main/Resour>

  An unhandled exception was thrown in the compiler.
  Please file a crash report here:
  https://github.com/scala/scala3/issues/new/choose
  For non-enriched exceptions, compile with -Xno-enrich-error-messages.


     while compiling: /nix/var/nix/builds/nix-63932-2468348747/effekt-src/effekt/js/target/scala-3.3.6/src_managed/main/Resources.scala
        during phase: pickler
                mode: Mode(ImplicitsEnabled,ReadPositions)
     library version: version 2.13.16
    compiler version: version 3.3.6
            settings: -Werror true -Xsemanticdb true -bootclasspath /nix/var/nix/builds/nix-63932-2468348747/tmp.aM6MNA3Y1w/project/.coursier/https/rep>

[error] ## Exception when compiling 111 sources to /nix/var/nix/builds/nix-63932-2468348747/effekt-src/effekt/js/target/scala-3.3.6/classes
[error] java.lang.ArrayIndexOutOfBoundsException: arraycopy: last destination index 3955373 out of bounds for char[2097152]
[error] java.base/java.lang.System.arraycopy(Native Method)
[error] scala.Array$.copy(Array.scala:110)

[jiribenes]

I might have a better solution: generate a JSON { ..."<path>": "<file contents>" } and then import it from JavaScript.

[jiribenes]

this doesn't look like it actually embeds the stdlib-resources.json, we might need a bundler or also copy that file onto the website...