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

pezcumulus/teyrchains/pezpallets/identity-kyc/src/mock.rs

@@ -1,8 +1,5 @@
 use crate as pezpallet_identity_kyc;
-use pezframe_support::{
-	construct_runtime, derive_impl, parameter_types,
-	traits::ConstU128,
-};
+use pezframe_support::{construct_runtime, derive_impl, parameter_types, traits::ConstU128};
 use pezframe_system::EnsureRoot;
 use pezsp_core::H256;
 use pezsp_runtime::BuildStorage;