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/pezpallets/validator-pool/src/tests.rs

@@ -637,7 +637,9 @@ fn shadow_comparison_recorded() {
 		let comparison = ValidatorPool::shadow_comparison();
 		assert!(comparison.is_some());
 		let comp = comparison.unwrap();
-		assert!(comp.overlap_count > 0 || !comp.tnpos_only.is_empty() || !comp.npos_only.is_empty());
+		assert!(
+			comp.overlap_count > 0 || !comp.tnpos_only.is_empty() || !comp.npos_only.is_empty()
+		);
 	});
 }