fix: add resilient Starknet mainnet RPC fallbacks

The sole configured Starknet mainnet RPC (rpc.starknet.lava.build/rpc/v0_9)
has been discontinued and now returns intermittent malformed/non-JSON bodies
and StarknetError(BlockNotFound), wedging the relayer and validator
contract-sync cursors. Added healthy public fallbacks (publicnode, cartridge;
both at chain head, spec 0.10.2) ahead of the Lava endpoint.

Author: haggis-hyperlane

.changeset/starknet-rpc-fallbacks.md

@@ -0,0 +1,5 @@
+---
+'@hyperlane-xyz/registry': patch
+---
+
+Added resilient public RPC fallbacks for Starknet mainnet ahead of the discontinued Lava endpoint.

chains/metadata.yaml

@@ -8458,6 +8458,8 @@ starknet:
     symbol: STRK
   protocol: starknet
   rpcUrls:
+    - http: https://starknet-rpc.publicnode.com
+    - http: https://api.cartridge.gg/x/starknet/mainnet
     - http: https://rpc.starknet.lava.build:443/rpc/v0_9
   technicalStack: other
 starknetsepolia:

chains/starknet/metadata.yaml

@@ -24,5 +24,7 @@ nativeToken:
   symbol: STRK
 protocol: starknet
 rpcUrls:
+  - http: https://starknet-rpc.publicnode.com
+  - http: https://api.cartridge.gg/x/starknet/mainnet
   - http: https://rpc.starknet.lava.build:443/rpc/v0_9
 technicalStack: other