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/client/tracing/benches/common/mod.rs

@@ -71,13 +71,14 @@ fn parse_interest_cache_config() -> Option<tracing_log::InterestCacheConfig> {
 		let value = parts[1].trim();
 
 		match key {
-			"lru_cache_size" =>
+			"lru_cache_size" => {
 				if let Ok(size) = value.parse::<usize>() {
 					config = config.with_lru_cache_size(size);
 					eprintln!("Interest cache: lru_cache_size = {}", size);
 				} else {
 					eprintln!("Invalid lru_cache_size value '{}'", value);
-				},
+				}
+			},
 			"min_verbosity" => {
 				let level = match value.to_lowercase().as_str() {
 					"error" => Some(Level::Error),