subxt-core crate (#1466)

* start migrating, broken

* first iteration of updating

* fmt and clippy

* add Composite<u32> decoding via scale value patch

* bump scale type gen versions

* fix decoding with new scale decode

* compiling with changed deps

* core utils, condig, client, metadata

* core crate compiling

* signer crate no once lock

* add core to no-std-tests, change imports

* broken commit, start pulling everything together in subxt

* port more things to subxt

* events in core crate, extrinsics sadly much more difficult

* almost all examples pass again

* dynamic values fix in examples

* fix no std issue and fmt

* remove unused dependencies

* fix lightclient impl

* runtime version refactor

* formatting and addressing nits

* more comments addressed

* update wasm example and no-std-signer tests

* other nits and error impl on signer errors

* fix feature flag

* fix runtime version refactor

* fix doc links

* fix integration tests

* fix feature flag gated client state

* fix native feature in CI

* fix lightclient utils

* make imports more lean in subxt-core

* integrate changes from subxt-core imports into subxt

* other changes in subxt simplify imports more

* fix  and docs

* doc false for cli

* fix clippy

* remove events block hash in tests

* codegen no-std support in generated code

* export alloc crate for no-std codegen

* fix doc test

* implement James comments

* remove std traits, use core traits instead

* address nits

* remove unusued dep in no-std tests

* fix Box import in no_std

* sp-crypto-hashing instead of sp-core-hashing

* bump scale-typegen, add no std codegen tests

* fix some things

* replace unmaintained derivative with derive_where to remove non-canonical warnings

* fmt

* remove unused dep

* fix deps

* update artifacts to fix type ID mismatches

* bump to latest scale-typegen

---------

Co-authored-by: James Wilson <james@jsdw.me>

codegen/src/api/constants.rs

@@ -5,6 +5,7 @@
 use heck::ToSnakeCase as _;
 use proc_macro2::TokenStream as TokenStream2;
 use quote::{format_ident, quote};
+use scale_typegen::typegen::ir::ToTokensWithSettings;
 use scale_typegen::TypeGenerator;
 use subxt_metadata::PalletMetadata;
 
@@ -31,7 +32,7 @@ use super::CodegenError;
 ///
 /// - `type_gen` - [`scale_typegen::TypeGenerator`] that contains settings and all types from the runtime metadata.
 /// - `pallet` - Pallet metadata from which the constants are generated.
-/// - `crate_path` - The crate path under which subxt is located, e.g. `::subxt` when using subxt as a dependency.
+/// - `crate_path` - The crate path under which the `subxt-core` crate is located, e.g. `::subxt::ext::subxt_core` when using subxt as a dependency.
 pub fn generate_constants(
     type_gen: &TypeGenerator,
     pallet: &PalletMetadata,
@@ -55,7 +56,9 @@ pub fn generate_constants(
                 ));
             };
 
-            let return_ty = type_gen.resolve_type_path(constant.ty())?;
+            let return_ty = type_gen
+                .resolve_type_path(constant.ty())?
+                .to_token_stream(type_gen.settings());
             let docs = constant.docs();
             let docs = type_gen
                 .settings()