CLI: dynamic signing reboot (#8384)

* Add keypair_util_from_path helper

* Cli: impl config.keypair as a trait object

* SDK: Add Debug and PartialEq for dyn Signer

* ClapUtils: Arg parsing from pubkey+signers to Presigner

* Impl Signers for &dyn Signer collections

* CLI: Add helper for getting signers from args

* CLI: Replace SigningAuthority with Signer trait-objs

* CLI: Drop disused signers command field

* CLI: Drop redundant tests

* Add clap validator that handles all current signer types

* clap_utils: Factor Presigner resolution to helper

* SDK: `From` for boxing Signer implementors to trait objects

* SDK: Derive `Clone` for `Presigner`

* Remove panic

* Cli: dedup signers in transfer for remote-wallet ergonomics

* Update docs vis-a-vis ASK changes

* Cli: update transaction types to use new dynamic-signer methods

* CLI: Fix tests No. 1

what to do about write_keypair outstanding

* Work around `CliConfig`'s signer not necessarily being a `Keypair`

* CLI: Fix tests No. 2

* Remove unused arg

* Remove unused methods

* Move offline arg constants upstream

* Make cli signing fallible

Co-authored-by: Trent Nelson <trent.a.b.nelson@gmail.com>

remote-wallet/src/ledger.rs

@@ -341,7 +341,7 @@ fn extend_and_serialize(derivation_path: &DerivationPath) -> Vec<u8> {
 pub fn get_ledger_from_info(
     info: RemoteWalletInfo,
 ) -> Result<Arc<LedgerWallet>, RemoteWalletError> {
-    let wallet_manager = initialize_wallet_manager();
+    let wallet_manager = initialize_wallet_manager()?;
     let _device_count = wallet_manager.update_devices()?;
     let devices = wallet_manager.list_devices();
     let (pubkeys, device_paths): (Vec<Pubkey>, Vec<String>) = devices