build: Replace wasm-pack

This is the beginning of PRQL#1836, replacing `wasm-pack` with https://crates.io/crates/substrate-wasm-builder. `wasm-pack` has been the source of lots of issues, makes builds slower -- in particular small code changes cause a very long iteration cycle in playground builds -- and is no longer maintanied.

It's a bit harder than I thought:
- We need to create the paths `bundler`, `node`, `web` paths ourselves, replacing [these lines](https://github.com/PRQL/prql/blob/5db61f45ad31ff5673fdfb7890cc3699d47940f9/bindings/prql-js/package.json#L20-L21), by calling `wasm-bindgen debug/wbuild/prql-js/prql_js.wasm --target=...`.
- We probably need some way of getting the `.wasm` file location, by reading `include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));` for the `WASM_BINARY` or `WASM_BINARY_BLOATY` constants. Ideally we'd do this at build time, all in the `build.rs` script; I'm not sure whether that's possible though.
- Possibly I'm figuring too much of this out on my own and it's done elsewhere? The precedent for this approach seems to be blockchain rather than JS applications...

bindings/prql-js/Cargo.toml

@@ -39,6 +39,9 @@ console_error_panic_hook = {version = "0.1.7", optional = true}
 [dev-dependencies]
 wasm-bindgen-test = "0.3.30"
 
+[build-dependencies]
+substrate-wasm-builder = "10.0.0"
+
 [package.metadata.cargo-udeps.ignore]
 development = ["wasm-bindgen-test"]
 

bindings/prql-js/build.rs

@@ -0,0 +1,13 @@
+fn main() {
+    {
+        substrate_wasm_builder::WasmBuilder::new()
+            // Tell the builder to build the project (crate) this `build.rs` is part of.
+            .with_current_project()
+            // Make sure to export the `heap_base` global, this is required by Substrate
+            .export_heap_base()
+            // Build the Wasm file so that it imports the memory (need to be provided by at instantiation)
+            .import_memory()
+            // Build it.
+            .build();
+    }
+}

bindings/prql-js/src/lib.rs

@@ -7,6 +7,8 @@ use std::str::FromStr;
 use prql_compiler::Target;
 use wasm_bindgen::prelude::*;
 
+include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));
+
 #[wasm_bindgen]
 pub fn compile(prql_query: &str, options: Option<CompileOptions>) -> Option<String> {
     return_or_throw(