feat: dual-chain staking score with XCM data pipeline

- Rewrite pezpallet-staking-score: StorageDoubleMap (AccountId x StakingSource),
  remove StakingInfoProvider trait, all data via receive_staking_details()
- Add StakingSource enum (RelayChain / AssetHub) for multi-source aggregation
- Add OnStakingDataUpdate callback trait for trust pallet integration
- Trust pallet: on_initialize hook for periodic batch updates,
  OnStakingDataUpdate impl triggers immediate score recalculation
- People Chain runtime: remove noop StakingInfoProvider, wire OnStakingUpdate = Trust
- Update weights for both pallets (conservative estimates incl. callback cost)
- spec_version 1_020_005 -> 1_020_006
- 57 tests passing (25 staking-score + 32 trust)

Cargo.lock

@@ -17858,20 +17858,12 @@ version = "1.0.0"
 dependencies = [
  "parity-scale-codec",
  "pezframe-benchmarking",
- "pezframe-election-provider-support",
  "pezframe-support",
  "pezframe-system",
  "pezkuwi-primitives",
- "pezpallet-bags-list",
  "pezpallet-balances",
- "pezpallet-session",
- "pezpallet-staking",
- "pezpallet-timestamp",
- "pezsp-core",
  "pezsp-io",
- "pezsp-npos-elections",
  "pezsp-runtime",
- "pezsp-staking",
  "pezsp-std",
  "scale-info",
  "serde",