fix: Complete snowbridge pezpallet rebrand and critical bug fixes

- snowbridge-pezpallet-* → pezsnowbridge-pezpallet-* (201 refs)
- pallet/ directories → pezpallet/ (4 locations)
- Fixed pezpallet.rs self-include recursion bug
- Fixed sc-chain-spec hardcoded crate name in derive macro
- Reverted .pezpallet_by_name() to .pallet_by_name() (subxt API)
- Added BizinikiwiConfig type alias for zombienet tests
- Deleted obsolete session state files

Verified: pezsnowbridge-pezpallet-*, pezpallet-staking,
pezpallet-staking-async, pezframe-benchmarking-cli all pass cargo check

pezbridges/modules/teyrchains/src/proofs.rs

@@ -0,0 +1,81 @@
+// Copyright 2019-2021 Parity Technologies (UK) Ltd.
+// This file is part of Parity Bridges Common.
+
+// Parity Bridges Common is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity Bridges Common is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Tools for teyrchain head proof verification.
+
+use crate::{Config, GrandpaPalletOf, RelayBlockHash, RelayBlockHasher};
+use bp_header_pez_chain::{HeaderChain, HeaderChainError};
+use bp_pezkuwi_core::teyrchains::{ParaHead, ParaId};
+use pezbp_runtime::{RawStorageProof, StorageProofChecker, StorageProofError};
+use bp_teyrchains::teyrchain_head_storage_key_at_source;
+use codec::Decode;
+use pezframe_support::traits::Get;
+
+/// Abstraction over storage proof manipulation, hiding implementation details of actual storage
+/// proofs.
+pub trait StorageProofAdapter<T: Config<I>, I: 'static> {
+	/// Read and decode optional value from the proof.
+	fn read_and_decode_optional_value<D: Decode>(
+		&mut self,
+		key: &impl AsRef<[u8]>,
+	) -> Result<Option<D>, StorageProofError>;
+
+	/// Checks if each key was read.
+	fn ensure_no_unused_keys(self) -> Result<(), StorageProofError>;
+
+	/// Read teyrchain head from storage proof.
+	fn read_teyrchain_head(
+		&mut self,
+		teyrchain: ParaId,
+	) -> Result<Option<ParaHead>, StorageProofError> {
+		let teyrchain_head_key =
+			teyrchain_head_storage_key_at_source(T::ParasPalletName::get(), teyrchain);
+		self.read_and_decode_optional_value(&teyrchain_head_key)
+	}
+}
+
+/// Actual storage proof adapter for teyrchain proofs.
+pub type TeyrchainsStorageProofAdapter<T, I> = RawStorageProofAdapter<T, I>;
+
+/// A `StorageProofAdapter` implementation for raw storage proofs.
+pub struct RawStorageProofAdapter<T: Config<I>, I: 'static> {
+	storage: StorageProofChecker<RelayBlockHasher>,
+	_dummy: pezsp_std::marker::PhantomData<(T, I)>,
+}
+
+impl<T: Config<I>, I: 'static> RawStorageProofAdapter<T, I> {
+	/// Try to create a new instance of `RawStorageProofAdapter`.
+	pub fn try_new_with_verified_storage_proof(
+		relay_block_hash: RelayBlockHash,
+		storage_proof: RawStorageProof,
+	) -> Result<Self, HeaderChainError> {
+		GrandpaPalletOf::<T, I>::verify_storage_proof(relay_block_hash, storage_proof)
+			.map(|storage| RawStorageProofAdapter::<T, I> { storage, _dummy: Default::default() })
+	}
+}
+
+impl<T: Config<I>, I: 'static> StorageProofAdapter<T, I> for RawStorageProofAdapter<T, I> {
+	fn read_and_decode_optional_value<D: Decode>(
+		&mut self,
+		key: &impl AsRef<[u8]>,
+	) -> Result<Option<D>, StorageProofError> {
+		self.storage.read_and_decode_opt_value(key.as_ref())
+	}
+
+	fn ensure_no_unused_keys(self) -> Result<(), StorageProofError> {
+		self.storage.ensure_no_unused_nodes()
+	}
+}