style: Migrate to stable-only rustfmt configuration

- Remove nightly-only features from .rustfmt.toml and vendor/ss58-registry/rustfmt.toml
- Removed features: imports_granularity, wrap_comments, comment_width,
  reorder_impl_items, spaces_around_ranges, binop_separator,
  match_arm_blocks, trailing_semicolon, trailing_comma
- Format all 898 affected files with stable rustfmt
- Ensures long-term reliability without nightly toolchain dependency

pezbridges/modules/relayers/src/extension/mod.rs

@@ -407,11 +407,12 @@ where
 					"Has registered reward"
 				);
 			},
-			RelayerAccountAction::Slash(relayer, slash_account) =>
+			RelayerAccountAction::Slash(relayer, slash_account) => {
 				RelayersPallet::<R, C::BridgeRelayersPalletInstance>::slash_and_deregister(
 					&relayer,
 					ExplicitOrAccountParams::Params(slash_account),
-				),
+				)
+			},
 		}
 
 		Ok(Weight::zero())
@@ -676,8 +677,8 @@ mod tests {
 					test_lane_id(),
 				)
 				.unwrap()
-				.last_delivered_nonce() +
-					1,
+				.last_delivered_nonce()
+					+ 1,
 				nonces_end: best_message,
 			}),
 			messages_count: 1,