Scaffold agent permissions, approval comments, and hiring governance types

Add pending_approval agent status, permissions jsonb column, and AgentPermissions
type with canCreateAgents flag. Add approval_comments table and ApprovalComment
type. Extend approval statuses with revision_requested. Add validators for
permission updates, approval revision requests, resubmission, and approval
comments. Add requireBoardApprovalForNewAgents to company update schema.

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

packages/db/src/schema/approval_comments.ts

@@ -0,0 +1,26 @@
+import { pgTable, uuid, text, timestamp, index } from "drizzle-orm/pg-core";
+import { companies } from "./companies.js";
+import { approvals } from "./approvals.js";
+import { agents } from "./agents.js";
+
+export const approvalComments = pgTable(
+  "approval_comments",
+  {
+    id: uuid("id").primaryKey().defaultRandom(),
+    companyId: uuid("company_id").notNull().references(() => companies.id),
+    approvalId: uuid("approval_id").notNull().references(() => approvals.id),
+    authorAgentId: uuid("author_agent_id").references(() => agents.id),
+    authorUserId: text("author_user_id"),
+    body: text("body").notNull(),
+    createdAt: timestamp("created_at", { withTimezone: true }).notNull().defaultNow(),
+    updatedAt: timestamp("updated_at", { withTimezone: true }).notNull().defaultNow(),
+  },
+  (table) => ({
+    companyIdx: index("approval_comments_company_idx").on(table.companyId),
+    approvalIdx: index("approval_comments_approval_idx").on(table.approvalId),
+    approvalCreatedIdx: index("approval_comments_approval_created_idx").on(
+      table.approvalId,
+      table.createdAt,
+    ),
+  }),
+);