Use Julia 1.12, Pkg workspaces and JuliaC sans trimming (#2629)

Supersedes #2440.

Let's see about the tests. From the original PR this point stands:

- One PR should give 1.12 compat since `julia_init` is removed there. We
need to update our [Rust
wrapper](https://github.com/Deltares/Ribasim/blob/ce73b6c358374477170d86e3c36195a72b9a5d04/build/cli/src/main.rs#L55-L57)
for that as well.

This may apply to `ribasim_api` package as well as the Rust wrapper.
See also https://github.com/JuliaLang/PackageCompiler.jl/pull/1047/files
and https://docs.julialang.org/en/v1/manual/embedding/

Author: visr

.vscode/settings.json

@@ -63,7 +63,7 @@
         "Ribasim"
     ],
     "files.insertFinalNewline": true,
-    "julia.executablePath": "julia +1.11.7",
+    "julia.executablePath": "julia +1.12.0",
     "julia.additionalArgs": [
         "--check-bounds=yes"
     ],