Generify Account::client over Rc, Arc

[cycraig]

Description of change

This changes the Account and its related structs to be generic over Arc<Client> and Rc<Client> so that we can use WasmClient directly without needing to clone the internal Client.

Unfortunately, to make a long story short: we cannot implement a higher kinded type for Arc/Rc over unsized types, namely dyn Storage in the Account, due to the lack of CoerceUnsized in stable Rust.

I believe that without implementing CoerceUnsized for whatever SharedPtrUnsized trait we come up with, we will be unable to circumvent the type-mismatch error when trying to pass a concrete instance like Arc<MemStore>.
Example:

AccountSetup::new(
	Arc::new(MemStore::new()),
	Arc::new(
	  ClientBuilder::new()
		.network(network)
		.node_sync_disabled()
		.build()
		.await
		.unwrap(),
	),
	AccountConfig::new(),
)

error[E0271]: type mismatch resolving `<account::account::ArcPtr as account::account::SharedPtrUnsized<(dyn storage::traits::Storage + 'static)>>::Ptr == std::sync::Arc<storage::memstore::MemStore>`
  --> identity-account\src\tests\updates.rs:39:3
   |
39 | /   AccountSetup::new(
40 | |     Arc::new(MemStore::new()),
41 | |     Arc::new(
42 | |       ClientBuilder::new()
...  |
49 | |     AccountConfig::new().testmode(true),
50 | |   )
   | |___^ type mismatch resolving `<account::account::ArcPtr as account::account::SharedPtrUnsized<(dyn storage::traits::Storage + 'static)>>::Ptr == std::sync::Arc<storage::memstore::MemStore>`
   |
note: expected this to be `std::sync::Arc<(dyn storage::traits::Storage + 'static)>`
  --> identity-account\src\account\account.rs:72:14
   |
72 |   type Ptr = Arc<T>;
   |              ^^^^^^
   = note: expected struct `std::sync::Arc<(dyn storage::traits::Storage + 'static)>`
              found struct `std::sync::Arc<storage::memstore::MemStore>`

The archery crate also suffers from this limitation. There is no indication that CoerceUnsized will be stabilized any time soon.

https://stackoverflow.com/questions/69500407/trait-object-causing-type-mismatch
https://doc.rust-lang.org/std/ops/trait.CoerceUnsized.html

Given the above, I chose to implement the same "poor-man's higher kinded type" approach I used for the Resolver in #594, which only works for Arc<Client>/Rc<Client> due to the same issue.

Type of change

• Bug fix (a non-breaking change which fixes an issue)
• Enhancement (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Fix

How the change has been tested

Tests and examples pass locally.

Change checklist

• I have followed the contribution guidelines for this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[cycraig]

Windows build-and-test job fails due to scoop, fixed on dev already and in the epic branch with #708, pending review.

[PhilippGackstatter]

Looks good to me!