feat: Rebrand Polkadot/Substrate references to PezkuwiChain

This commit systematically rebrands various references from Parity Technologies'
Polkadot/Substrate ecosystem to PezkuwiChain within the kurdistan-sdk.

Key changes include:
- Updated external repository URLs (zombienet-sdk, parity-db, parity-scale-codec, wasm-instrument) to point to pezkuwichain forks.
- Modified internal documentation and code comments to reflect PezkuwiChain naming and structure.
- Replaced direct references to  with  or specific paths within the  for XCM, Pezkuwi, and other modules.
- Cleaned up deprecated  issue and PR references in various  and  files, particularly in  and  modules.
- Adjusted image and logo URLs in documentation to point to PezkuwiChain assets.
- Removed or rephrased comments related to external Polkadot/Substrate PRs and issues.

This is a significant step towards fully customizing the SDK for the PezkuwiChain ecosystem.

bizinikiwi/primitives/arithmetic/fuzzer/src/per_thing_mult_fraction.rs

@@ -0,0 +1,69 @@
+// This file is part of Bizinikiwi.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! # Running
+//! Running this fuzzer can be done with `cargo hfuzz run per_thing_mult_fraction`. `honggfuzz` CLI
+//! options can be used by setting `HFUZZ_RUN_ARGS`, such as `-n 4` to use 4 threads.
+//!
+//! # Debugging a panic
+//! Once a panic is found, it can be debugged with
+//! `cargo hfuzz run-debug per_thing_mult_fraction hfuzz_workspace/per_thing_mult_fraction/*.fuzz`.
+
+use honggfuzz::fuzz;
+use pezsp_arithmetic::{PerThing, Perbill, Percent, Perquintill, *};
+
+/// Tries to disprove `(n / d) * d <= n` for any `PerThing`s.
+fn main() {
+	loop {
+		fuzz!(|data: (u128, u128)| {
+			let (n, d) = (data.0.min(data.1), data.0.max(data.1).max(1));
+
+			check_mul::<PerU16>(n, d);
+			check_mul::<Percent>(n, d);
+			check_mul::<Perbill>(n, d);
+			check_mul::<Perquintill>(n, d);
+
+			check_reciprocal_mul::<PerU16>(n, d);
+			check_reciprocal_mul::<Percent>(n, d);
+			check_reciprocal_mul::<Perbill>(n, d);
+			check_reciprocal_mul::<Perquintill>(n, d);
+		})
+	}
+}
+
+/// Checks that `(n / d) * d <= n`.
+fn check_mul<P: PerThing>(n: u128, d: u128)
+where
+	P: PerThing + core::ops::Mul<u128, Output = u128>,
+{
+	let q = P::from_rational_with_rounding(n, d, Rounding::Down).unwrap();
+	assert!(q * d <= n, "{:?} * {:?} <= {:?}", q, d, n);
+}
+
+/// Checks that `n / (n / d) >= d`.
+fn check_reciprocal_mul<P: PerThing>(n: u128, d: u128)
+where
+	P: PerThing + core::ops::Mul<u128, Output = u128>,
+{
+	let q = P::from_rational_with_rounding(n, d, Rounding::Down).unwrap();
+	if q.is_zero() {
+		return;
+	}
+
+	let r = q.saturating_reciprocal_mul_floor(n);
+	assert!(r >= d, "{} / ({} / {}) != {} but {}", n, n, d, d, r);
+}