Add support for XLS-85 Token Escrow (#5185)

- Specification: https://github.com/XRPLF/XRPL-Standards/pull/272
- Amendment: `TokenEscrow`
- Enables escrowing of IOU and MPT tokens in addition to native XRP.
- Allows accounts to lock issued tokens (IOU/MPT) in escrow objects, with support for freeze, authorization, and transfer rates.
- Adds new ledger fields (`sfLockedAmount`, `sfIssuerNode`, etc.) to track locked balances for IOU and MPT escrows.
- Updates EscrowCreate, EscrowFinish, and EscrowCancel transaction logic to support IOU and MPT assets, including proper handling of trustlines and MPT authorization, transfer rates, and locked balances.
- Enforces invariant checks for escrowed IOU/MPT amounts.
- Extends GatewayBalances RPC to report locked (escrowed) balances.

src/test/app/AMM_test.cpp

@@ -3651,10 +3651,10 @@ private:
         // Can't pay into AMM with escrow.
         testAMM([&](AMM& ammAlice, Env& env) {
             auto const baseFee = env.current()->fees().base;
-            env(escrow(carol, ammAlice.ammAccount(), XRP(1)),
-                condition(cb1),
-                finish_time(env.now() + 1s),
-                cancel_time(env.now() + 2s),
+            env(escrow::create(carol, ammAlice.ammAccount(), XRP(1)),
+                escrow::condition(escrow::cb1),
+                escrow::finish_time(env.now() + 1s),
+                escrow::cancel_time(env.now() + 2s),
                 fee(baseFee * 150),
                 ter(tecNO_PERMISSION));
         });