remove substrate compat (#1850)

* remove substrate compat

* add hacky example

* simplify substrate-compat example

* simplify substrate-compat example

* cargo fmt

* fix build

* add more examples

* fix nit

* fix test build

* Update subxt/examples/substrate_compat_signer.rs

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

* keep only polkadot signer example

* remove more substrate compat related stuff

* fix example

* link to substrate signer example in book

* Update subxt/src/book/usage/transactions.rs

* Update subxt/src/book/usage/transactions.rs

* address grumbles

* fix nits

---------

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

metadata/Cargo.toml

@@ -32,7 +32,7 @@ criterion = { workspace = true }
 scale-info = { workspace = true, features = ["bit-vec"] }
 
 [lib]
-# Without this, libtest cli opts interfere with criteron benches:
+# Without this, libtest cli opts interfere with criterion benches:
 bench = false
 
 [[bench]]