Upgrade to v5 schema

Now uses:
* ipld direct_by_leaf StateDB for basic queries
* trie_by_cid StateDB for trie slice and proof queries

Also:
* vulcanize => cerc refactor
* Backend method to close dbs
* state tests are in multiple packages, to allow separate ginkgo suites
* removes gap-filler module
* integration tests and github workflows
* run stack-orchestrator for testnet
* fix various issues with tests, hardhat server, dockerfile
* fix cmd flags / env vars
* fix flaky tests and clean up code
* remove unused code, scripts
* remove outdated docs
* update version

test/contract/Dockerfile

@@ -1,4 +1,5 @@
-FROM node:14
+# Downgrade from 18.16, see https://github.com/NomicFoundation/hardhat/issues/3877
+FROM node:18.15-slim
 
 ARG ETH_ADDR
 ENV ETH_ADDR $ETH_ADDR
@@ -11,4 +12,4 @@ RUN npm run compile && ls -lah
 
 EXPOSE 3000
 
-ENTRYPOINT ["npm", "start"]
+ENTRYPOINT ["node", "src/index.js"]