cache knobs: env-parameterize geth/op-geth --cache (default 1024 = geth's own), l2geth --cache (default 8192 = previous hardcoded), nethermind MEMORYHINT (default 2048000000)

All defaults preserve current effective behavior - this deploy is a rendering no-op
until a host_var overrides a value. Part of the resource-optimizer knob rollout
(resource-optimizer/knob-manifest.yaml is the registry; verify_manifest.py enforces
default sync between templates and envfile).

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

op/geth/celo-sepolia-op-geth-pruned-pebble-hash.yml

@@ -88,6 +88,7 @@ services:
     entrypoint: /bin/sh -c '[ -f /config/genesis.json ] && geth --db.engine=pebble --gcmode=full --datadir /data init --state.scheme=hash /config/genesis.json; exec geth "$@"' --
     command:
       - --bootnodes=enode://7fd35dfea27042fe008c74ea97c7a41254b293152730419a6e9bcd84bb03c7ced418c1043e2ef6ad63d2facca6fbdacfbf7c4bfcf33ee7e9a0e6b7eb0617595d@34.169.104.197:30303,enode://151bcf170585971fc78129d9c16af355a1a53e1c825ce1ac20700ea754aa33eda60ca83de6f954bfed8d36c53f33295d93dbc3da9d549d6547d09467806b4b3d@104.199.124.11:30303,enode://aa5fb766438ac5a0354eb2eec1c0c002b56bb2ce7ed44f0e76e019cbb931222faa9ecfb0fa0055c0c62a2fcf04492d4129349a1045dfef140585250281885e4b@34.83.115.97:30303,enode://27c81ca466c99016d1595429afc68d66afb3ed9d5a2dd7f6a7797db23a4c826546a177b69b4932f3a75ce374b09d8ccc5b52dad615b3c47dbb8f6217d79ded22@35.247.1.226:30303
+      - --cache=${CELO_SEPOLIA_OP_GETH_PRUNED_PEBBLE_HASH_CACHE:-1024}
       - --datadir=/data
       - --db.engine=pebble
       - --gcmode=full