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/test-utils/runtime/transaction-pool/src/lib.rs

@@ -397,8 +397,9 @@ impl ChainApi for TestApi {
 					))));
 				}
 			},
-			Ok(None) =>
-				return Ok(Err(TransactionValidityError::Invalid(InvalidTransaction::Custom(2)))),
+			Ok(None) => {
+				return Ok(Err(TransactionValidityError::Invalid(InvalidTransaction::Custom(2))))
+			},
 			Err(e) => return Err(e),
 		}
 
@@ -484,8 +485,9 @@ impl ChainApi for TestApi {
 		at: &BlockId<Self::Block>,
 	) -> Result<Option<NumberFor<Self::Block>>, Error> {
 		Ok(match at {
-			generic::BlockId::Hash(x) =>
-				self.chain.read().block_by_hash.get(x).map(|b| *b.header.number()),
+			generic::BlockId::Hash(x) => {
+				self.chain.read().block_by_hash.get(x).map(|b| *b.header.number())
+			},
 			generic::BlockId::Number(num) => Some(*num),
 		})
 	}
@@ -496,10 +498,11 @@ impl ChainApi for TestApi {
 	) -> Result<Option<<Self::Block as BlockT>::Hash>, Error> {
 		Ok(match at {
 			generic::BlockId::Hash(x) => Some(*x),
-			generic::BlockId::Number(num) =>
+			generic::BlockId::Number(num) => {
 				self.chain.read().block_by_number.get(num).and_then(|blocks| {
 					blocks.iter().find(|b| b.1.is_best()).map(|b| b.0.header().hash())
-				}),
+				})
+			},
 		})
 	}