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/core/backing/src/lib.rs

@@ -831,7 +831,7 @@ async fn validate_and_make_available(
 
 	let pov = match pov {
 		PoVData::Ready(pov) => pov,
-		PoVData::FetchFromValidator { from_validator, candidate_hash, pov_hash } =>
+		PoVData::FetchFromValidator { from_validator, candidate_hash, pov_hash } => {
 			match request_pov(
 				&mut sender,
 				relay_parent,
@@ -854,7 +854,8 @@ async fn validate_and_make_available(
 				},
 				Err(err) => return Err(err),
 				Ok(pov) => pov,
-			},
+			}
+		},
 	};
 
 	let v = {
@@ -945,10 +946,12 @@ async fn handle_communication<Context>(
 		CandidateBackingMessage::Statement(relay_parent, statement) => {
 			handle_statement_message(ctx, state, relay_parent, statement, metrics).await?;
 		},
-		CandidateBackingMessage::GetBackableCandidates(requested_candidates, tx) =>
-			handle_get_backable_candidates_message(state, requested_candidates, tx, metrics)?,
-		CandidateBackingMessage::CanSecond(request, tx) =>
-			handle_can_second_request(ctx, state, request, tx).await,
+		CandidateBackingMessage::GetBackableCandidates(requested_candidates, tx) => {
+			handle_get_backable_candidates_message(state, requested_candidates, tx, metrics)?
+		},
+		CandidateBackingMessage::CanSecond(request, tx) => {
+			handle_can_second_request(ctx, state, request, tx).await
+		},
 	}
 
 	Ok(())

pezkuwi/node/core/backing/src/tests/mod.rs

@@ -51,8 +51,9 @@ struct TestLeaf {
 
 fn table_statement_to_primitive(statement: TableStatement) -> Statement {
 	match statement {
-		TableStatement::Seconded(committed_candidate_receipt) =>
-			Statement::Seconded(committed_candidate_receipt),
+		TableStatement::Seconded(committed_candidate_receipt) => {
+			Statement::Seconded(committed_candidate_receipt)
+		},
 		TableStatement::Valid(candidate_hash) => Statement::Valid(candidate_hash),
 	}
 }