[tracking] adopt BlockNumberProvider for the pallets migrating to AH

[muharem]

Some of the pallets migrating from the Relay Chain to the Asset Hub require a more deterministic clock than what a parachain can provide. To address this, the decision was made to adapt these pallets to use a configurable block number provider, which can be set to the Relay Chain’s block number provider for greater determinism. (For more details, see the discussions at #3268). This approach will also simplify the migration of pallets' state from the Relay Chain to the Asset Hub since, in most cases, block numbers won’t require mapping.

Task:

Adapt BlockNumberProvider for the pallets migrating to the Asset Hub:

• Introduce a BlockNumberProvider configuration parameter and use its current_block_number function as the time reference instead of System::<T>::block_number().
• Ensure pallet hooks like on_initialize(n) are compatible with the BlockNumberProvider and can handle cases when the hook isn’t called on every tick (e.g., adapt conditions that rely on exact matches like compilation_time == BlockNumberProvider::current_block_number()).
• Review all instances of generic block number types, ensuring they reference the correct type (e.g., BlockNumberProvider::BlockNumber when migrated to BlockNumberProvider).
• Update documentation for calls with block number parameters, configuration settings like BountyUpdatePeriod, and storage fields. Documentation should clarify for users that block numbers refer to those from Config::BlockNumberProvider, which may come from either the local parachain or the Relay Chain.

Reference PR: #3970

Pallet list:

(when you start to work on a pallet, pul your name next to it or leave a comment)

• pallet_scheduler - Update Scheduler to Support Relay Chain Block Number Provider #6362
• pallet_treasury - Update Treasury to Support Relay Chain Block Number Provider #3970
• pallet_bounties - Update Treasury to Support Relay Chain Block Number Provider #3970
• pallet_child_bounties - Update Treasury to Support Relay Chain Block Number Provider #3970
• pallet_referenda
• pallet_conviction_voting
• pallet_election_provider_multi_phase
• pallet_nis
• pallet_nomination_pools
• pallet_recovery
• pallet_society

[AurevoirXavier]

Love to take on some tasks once the #3970 is merged as a standard to follow.

[muharem]

@AurevoirXavier it is merged now