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

bizinikiwi/primitives/storage/src/lib.rs

@@ -298,8 +298,9 @@ impl ChildInfo {
 	/// this trie.
 	pub fn prefixed_storage_key(&self) -> PrefixedStorageKey {
 		match self {
-			ChildInfo::ParentKeyId(ChildTrieParentKeyId { data }) =>
-				ChildType::ParentKeyId.new_prefixed_key(data.as_slice()),
+			ChildInfo::ParentKeyId(ChildTrieParentKeyId { data }) => {
+				ChildType::ParentKeyId.new_prefixed_key(data.as_slice())
+			},
 		}
 	}