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

pezcumulus/client/consensus/aura/src/equivocation_import_queue.rs

@@ -177,8 +177,8 @@ where
 					let relay_parent =
 						match CumulusDigestItem::find_relay_block_identifier(pre_header.digest()) {
 							None => Default::default(),
-							Some(RelayBlockIdentifier::ByHash(h)) |
-							Some(RelayBlockIdentifier::ByStorageRoot {
+							Some(RelayBlockIdentifier::ByHash(h))
+							| Some(RelayBlockIdentifier::ByStorageRoot {
 								storage_root: h, ..
 							}) => h,
 						};
@@ -219,11 +219,12 @@ where
 						post_hash, slot
 					));
 				},
-				Err(e) =>
+				Err(e) => {
 					return Err(format!(
 						"Rejecting block ({:?}) with invalid seal ({:?})",
 						post_hash, e
-					)),
+					))
+				},
 			}
 		}