Use scale-encode and scale-decode to encode and decode based on metadata (#842)

* WIP EncodeAsType and DecodeAsType

* remove silly cli experiment code

* Get things finally compiling with EncodeAsType and DecodeAsType

* update codegen test and WrapperKeepOpaque proper impl (in case it shows up in codegen)

* fix tests

* accomodate scale-value changes

* starting to migrate to EncodeAsType/DecodeAsType

* static event decoding and tx encoding to use DecodeAsFields/EncodeAsFields

* some tidy up and add decode(skip) attrs where needed

* fix root event decoding

* #[codec(skip)] will do, and combine map_key stuff into storage_address since it's all specific to that

* fmt and clippy

* update Cargo.lock

* remove patched scale-encode

* bump scale-encode to 0.1 and remove unused dep in testing crate

* update deps and use released scale-decode

* update scale-value to latest to remove git branch

* Apply suggestions from code review

Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>

* remove sorting in derives/attr generation; spit them out in order given

* re-add derive sorting; it's a hashmap

* StaticTxPayload and DynamicTxPayload rolled into single Payload struct

* StaticStorageAddress and DynamicStorageAddress into single Address struct

* Fix storage address byte retrieval

* StaticConstantAddress and DynamicConstantAddress => Address

* Simplify storage codegen to fix test

* Add comments

* Alias to RuntimeEvent rather than making another, and prep for substituting call type

* remove unnecessary clone

* Fix docs and failing UI test

* root_bytes -> to_root_bytes

* document error case in StorageClient::address_bytes()

---------

Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>

subxt/src/metadata/mod.rs

@@ -4,8 +4,7 @@
 
 //! Types representing the metadata obtained from a node.
 
-mod decode_with_metadata;
-mod encode_with_metadata;
+mod decode_encode_traits;
 mod hash_cache;
 mod metadata_location;
 mod metadata_type;
@@ -14,7 +13,6 @@ pub use metadata_location::MetadataLocation;
 
 pub use metadata_type::{
     ErrorMetadata,
-    EventFieldMetadata,
     EventMetadata,
     InvalidMetadataError,
     Metadata,
@@ -22,12 +20,7 @@ pub use metadata_type::{
     PalletMetadata,
 };
 
-pub use decode_with_metadata::{
-    DecodeStaticType,
+pub use decode_encode_traits::{
     DecodeWithMetadata,
-};
-
-pub use encode_with_metadata::{
-    EncodeStaticType,
     EncodeWithMetadata,
 };