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

pezkuwi/node/network/collator-protocol/src/lib.rs

@@ -151,14 +151,16 @@ impl<Context> CollatorProtocolSubsystem {
 				.boxed()
 			},
 			#[cfg(feature = "experimental-collator-protocol")]
-			ProtocolSide::ValidatorExperimental { keystore, metrics } =>
+			ProtocolSide::ValidatorExperimental { keystore, metrics } => {
 				validator_side_experimental::run(ctx, keystore, metrics)
 					.map_err(|e| SubsystemError::with_origin("collator-protocol", e))
-					.boxed(),
-			ProtocolSide::Collator { peer_id, collator_pair, request_receiver_v2, metrics } =>
+					.boxed()
+			},
+			ProtocolSide::Collator { peer_id, collator_pair, request_receiver_v2, metrics } => {
 				collator_side::run(ctx, peer_id, collator_pair, request_receiver_v2, metrics)
 					.map_err(|e| SubsystemError::with_origin("collator-protocol", e))
-					.boxed(),
+					.boxed()
+			},
 			ProtocolSide::None => return DummySubsystem.start(ctx),
 		};