docs(iota-indexer): update ERD diagram and README #6932

Job	Run time
dprint-format	7s
diff	15s
typos / Spell Check with Typos	9s
turborepo / Lint, Build, and Test	1m 7s
turborepo / pnpm audit	13s
docs-lint	0s
docusaurus	0s
license-check	7s
release-notes-check	8s
e2e	0s
move-tests	0s
ledgernano	0s
vercel-deploy / Vercel Explorer Staging	0s
vercel-deploy / Vercel Explorer Preview	0s
vercel-deploy / Vercel UI Kit Preview	0s
vercel-deploy / Vercel UI Kit Production	0s
vercel-deploy / Vercel Wallet Dashboard Preview	0s
vercel-deploy / Vercel apps-backend Preview	0s
vercel-deploy / Vercel Wallet Dashboard Production	0s
vercel-deploy / Vercel apps-backend Production	0s
rust / deny / cargo deny (advisories)	7s
rust / deny / cargo deny (bans, licenses, sources)	7s
rust / rust-lints / cargo-sort	7s
rust / rust-lints / rustfmt	8s
rust / rust-lints / clippy	59s
rust / external-tests	0s
rust / rust-tests	0s
rust / execution-cut	0s
	3m 34s

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