Add shared types package

Shared TypeScript types, Zod validators, API contract definitions,
and constants used by both server and UI. Covers agents, goals,
issues, projects, and activity entities.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/shared/src/constants.ts

@@ -0,0 +1,33 @@
+export const AGENT_STATUSES = ["active", "idle", "offline", "error"] as const;
+export type AgentStatus = (typeof AGENT_STATUSES)[number];
+
+export const AGENT_ROLES = [
+  "engineer",
+  "designer",
+  "pm",
+  "qa",
+  "devops",
+  "general",
+] as const;
+export type AgentRole = (typeof AGENT_ROLES)[number];
+
+export const ISSUE_STATUSES = [
+  "backlog",
+  "todo",
+  "in_progress",
+  "in_review",
+  "done",
+  "cancelled",
+] as const;
+export type IssueStatus = (typeof ISSUE_STATUSES)[number];
+
+export const ISSUE_PRIORITIES = [
+  "critical",
+  "high",
+  "medium",
+  "low",
+] as const;
+export type IssuePriority = (typeof ISSUE_PRIORITIES)[number];
+
+export const GOAL_LEVELS = ["company", "team", "agent", "task"] as const;
+export type GoalLevel = (typeof GOAL_LEVELS)[number];