[indexer/verifier] Define verifier result status vocabulary

[FlowmemoryAI]

Objective

Define the first small status vocabulary for verifier outputs so dashboards, explorers, and future services can distinguish observed facts from verified claims.

Allowed folders

• services/verifier/
• services/indexer/ only for cross-reference terminology
• docs/ARCHITECTURE.md only for a short cross-link
• docs/SECURITY_MODEL.md only for trust-boundary notes

Forbidden folders

• contracts/
• apps/
• hardware/
• crypto/
• research/
• Production verifier runtime, proof systems, token incentives, deployment config

Acceptance criteria

• The vocabulary includes observed, verified, unresolved, unsupported, failed, and reorged or equivalent terms.
• Each status has a precise meaning and minimum evidence requirement.
• The document explains that off-chain artifacts must be checked against emitted commitments.
• No API, database, or UI implementation is added.

Risk level

Medium

Recommended worktree/agent

E:\FlowMemory\flowmemory-indexer / Services Agent

Scope guard

Keep this as a terminology/spec task. Do not introduce verifier economics or a proof network.