feat(p7): AI tables + enums + migration + events + InferencePort contract

Task 7.1: 7 AI-proposal-layer tables (IiosAiJob, IiosAiModelRun, IiosAiArtifact,
IiosAiClaim, IiosAiEvidenceLink, IiosAiToolCall, IiosEmbeddingRef) + enums;
migration ai-init. Adds ai.job.created / ai.artifact.proposed / ai.artifact.accepted
events and a standalone InferencePort contract (not part of sealed IiosPlatformPorts).
resetDb truncates the new tables.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/iios-contracts/src/inference.ts

@@ -0,0 +1,61 @@
+/**
+ * The AI inference port (P7). A standalone contract — deliberately NOT part of the
+ * sealed `IiosPlatformPorts`: AI is an internal "AI Factory" whose model execution
+ * routes through the Capability Broker in P9. In P7 it is a faked, deterministic,
+ * golden provider (no network). Every result carries the provenance the critics
+ * mandate (model/prompt version, tokens, cost, confidence, abstention, evidence).
+ */
+
+export type AiJobType = 'CLASSIFY' | 'SUMMARIZE' | 'EXTRACT';
+
+export type AiArtifactType = 'CLASSIFICATION' | 'SUMMARY' | 'TRANSCRIPT' | 'DIGEST' | 'EXTRACTION';
+
+export type AiClaimType = 'MODERATION_FLAG' | 'EVENT' | 'FAQ' | 'INTENT' | 'PRIORITY';
+
+export interface InferenceRequest {
+  jobType: AiJobType;
+  text: string;
+  purpose: string;
+  scopeId: string;
+  /** The kernel interaction this inference is about — used as the default evidence source. */
+  interactionId?: string;
+}
+
+export interface InferenceClaim {
+  claimType: AiClaimType;
+  claimJson: Record<string, unknown>;
+  confidence: number;
+}
+
+export interface InferenceEvidence {
+  sourceType: string;
+  sourceId: string;
+  spanRef?: string;
+  relevanceScore?: number;
+}
+
+export interface InferenceModelRun {
+  model: string;
+  modelVersion: string;
+  promptVersion: string;
+  tokensIn: number;
+  tokensOut: number;
+  costUnits: number;
+  latencyMs: number;
+}
+
+export interface InferenceResult {
+  artifactType: AiArtifactType;
+  content: unknown;
+  confidence: number;
+  explanation?: string;
+  /** Set when the model declines to assert a claim (Scenario 7 abstention). */
+  abstentionReason?: string;
+  claims: InferenceClaim[];
+  evidence: InferenceEvidence[];
+  modelRun: InferenceModelRun;
+}
+
+export interface InferencePort {
+  infer(req: InferenceRequest): Promise<InferenceResult>;
+}