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/primitives/header-chain/src/justification/verification/mod.rs

@@ -242,8 +242,8 @@ trait JustificationVerifier<Header: HeaderT> {
 		justification: &GrandpaJustification<Header>,
 	) -> Result<(), Error> {
 		// ensure that it is justification for the expected header
-		if (justification.commit.target_hash, justification.commit.target_number) !=
-			finalized_target
+		if (justification.commit.target_hash, justification.commit.target_number)
+			!= finalized_target
 		{
 			return Err(Error::InvalidJustificationTarget);
 		}