dispatch as emergency admin

[mrq1911]

add function similar to dispatch as aave admin that will allow TC to act as some address, which can be then configured in smart contracts as emergency admin that could pause some market for example

[dmoka]

Spec: dispatch_as_emergency_admin for TC

Motivation

The current path to interact with Aave contracts is dispatch_as_aave_manager, which requires an EconomicParameters referendum which might take several days. TC needs a faster path to react to emergencies.

Design

Add a new dispatch_as_emergency_admin extrinsic to the dispatcher pallet. It follows the exact same pattern as the existing dispatch_as_aave_manager, but:

• Origin: TC majority (or Root), instead of EconomicParameters
• Account: A separate configurable emergency admin address, instead of the aave manager address

On the Aave side, this address will be registered as the emergency admin via ACLManager.addEmergencyAdmin().

Changes

1. Pallet config (pallets/dispatcher/src/lib.rs)

Add two new associated types to the Config trait:

type EmergencyAdminOrigin: EnsureOrigin<Self::RuntimeOrigin>;
type DefaultEmergencyAdminAccount: Get<Self::AccountId>;

2. Storage (pallets/dispatcher/src/lib.rs)

Add one new storage item:

#[pallet::storage]
#[pallet::getter(fn emergency_admin_account)]
pub type EmergencyAdminAccount<T: Config> =
    StorageValue<_, T::AccountId, ValueQuery, T::DefaultEmergencyAdminAccount>;

3. Events (pallets/dispatcher/src/lib.rs)

Add two new event variants:

EmergencyAdminCallDispatched {
    call_hash: T::Hash,
    result: DispatchResultWithPostInfo,
},
EmergencyAdminAccountNoted {
    account: T::AccountId,
},

4. Extrinsics (pallets/dispatcher/src/lib.rs)

dispatch_as_emergency_admin

Mirrors dispatch_as_aave_manager. TC (or Root) calls this; the pallet dispatches the inner call as the emergency admin address.

#[pallet::call_index(5)]
#[pallet::weight({
    let call_weight = call.get_dispatch_info().call_weight;
    let call_len = call.encoded_size() as u32;
    T::WeightInfo::dispatch_as_emergency_admin(call_len)
        .saturating_add(call_weight)
})]
pub fn dispatch_as_emergency_admin(
    origin: OriginFor<T>,
    call: Box<<T as Config>::RuntimeCall>,
) -> DispatchResultWithPostInfo {
...
}

note_emergency_admin

Root-only setter for the emergency admin address. Mirrors note_aave_manager but adds an event.

#[pallet::call_index(6)]
#[pallet::weight(T::WeightInfo::note_emergency_admin())]
pub fn note_emergency_admin(origin: OriginFor<T>, account: T::AccountId) -> DispatchResult {
...
}

Aave proposal

For dispatch_as_emergency_admin to work, the address must also be registered in Aave's ACLManager. A separate governance proposal is needed (via aave-v3-deploy repo) that calls:

ACLManager.addEmergencyAdmin(0xaa7e0000000000000000000000000000000aa7e1)

For convenience, the emergency admin address is the aave manager address + 1 (0xaa7e...aa7e0 → 0xaa7e...aa7e1).