[codex] Build indexer verifier v0 fixture package

[FlowmemoryAI]

Summary

Builds the FlowMemory Indexer + Verifier V0 local service package as a fixture-first subsystem.

• Adds workspace scripts for shared, indexer, and verifier packages.
• Adds FlowPulse fixture receipt ingestion, ABI decoding, observation IDs, cursor IDs, duplicate handling, fixture reorg/finality state, and deterministic JSON persistence.
• Adds verifier artifact fixtures, resolver policy boundary, commitment checks, V0 report statuses, report digests, JSON schema, deterministic report output, and tests.
• Documents the MVP pipeline, observation/cursor/report identity model, verifier status vocabulary, crypto integration boundary, and non-goals.

Issues

Refs #13, #14, #43, #44, #45, #46, #47, #54, #55.

Validation

• npm install --package-lock-only --ignore-scripts
• npm test
• npm run e2e
• npm run demo:indexer
• npm run demo:verifier
• Determinism check across repeated npm run e2e runs:
  • services/indexer/out/indexer-state.json SHA256 2DE347FF219997669040B6AEB1A3A669D7AD25CC1FB2B271F2705420A6D321DA
  • services/verifier/out/reports.json SHA256 3F4E30DBEF2F20D88A2E926E5DC2BDDA88D05060CEE85B4A082E2EFA0ABA5529

Boundaries

• No live RPC required.
• No secrets or env files.
• No production database.
• No tokenomics.
• No verifier network or proof network.
• No contracts, hardware, apps, chain/L1, or production deployment edits.

[FlowmemoryAI]

Launch-core direction: please align this indexer/verifier PR with issue #65 and docs/V0_LAUNCH_ACCEPTANCE.md. Indexer-side completion should produce fixture-backed observations, MemorySignal, MemoryReceipt, RootflowTransition, verifier report, and dashboard-readable state.

[FlowmemoryAI]

Acceptance audit follow-up: the launch docs use external statuses verified and failed, while this PR appears to use valid and invalid internally. Please either expose the launch vocabulary externally or document the adapter mapping clearly, then provide the exact command/test evidence for Rootflow transition, report, and dashboard fixture outputs. The required evidence is tracked in docs/reviews/ROOTFLOW_FLOW_MEMORY_V0_ACCEPTANCE_AUDIT.md on PR #59.

[FlowmemoryAI]

Correction to the prior audit note: the status vocabulary risk is verified/failed in the launch docs versus valid/invalid in the current verifier work. Please either expose the launch vocabulary externally or document the adapter mapping clearly, then provide the exact command/test evidence for Rootflow transition, report, and dashboard fixture outputs.