monitoring scripts: protocol dispatch via registry slug + mantle/metis chainid fixes

- sync-status.sh: resolve protocol family from the compose x-upstreams chain
  label via the registry (reference-rpc-endpoint.sh --protocol) instead of
  path-substring guessing; legacy path detection kept as fallback for
  composes without a resolved label. Unknown families report
  'unsupported protocol: X' honestly instead of a bogus eth_chainId error.
  Aztec reference lookup falls back to slug urls when rollup_version is
  not in the registry.
- reference-rpc-endpoint.sh: new --chain <slug> (urls by registry key,
  works for idless non-EVM entries) and --protocol <slug> modes; existing
  chainid and --rollup-version lookups unchanged.
- mantle-sepolia: chainid 5001 -> 5003 (verified live: 0x138b), label and
  --networkid now correct
- metis-sepolia: label resolves via registry override (drpc chains.yaml
  carries wrong id 59901; live chain is 59902, verified via official RPC)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

metis-andromeda/l2geth/metis-andromeda-sepolia-l2geth-archive-leveldb-hash.yml

@@ -190,7 +190,7 @@ x-upstreams:
           frameSize: 20Mb
           msgSize: 50Mb
           url: $${WS_URL}
-    chain:
+    chain: metis-sepolia
     method-groups:
       enabled:
         - debug