feat(db): add feature flags schema for beta feature testing

Add feature_flags and feature_flag_access tables to support controlled
beta testing of new features in production without a separate test environment.

shared/db/schema/feature-flags.ts

@@ -0,0 +1,49 @@
+import {
+    pgTable,
+    serial,
+    varchar,
+    boolean,
+    text,
+    timestamp,
+    bigint,
+    integer,
+    index,
+} from 'drizzle-orm/pg-core';
+import { relations, type InferSelectModel } from 'drizzle-orm';
+
+export type FeatureFlag = InferSelectModel<typeof featureFlags>;
+export type FeatureFlagAccess = InferSelectModel<typeof featureFlagAccess>;
+
+export const featureFlags = pgTable('feature_flags', {
+    id: serial('id').primaryKey(),
+    name: varchar('name', { length: 100 }).notNull().unique(),
+    enabled: boolean('enabled').default(false).notNull(),
+    description: text('description'),
+    createdAt: timestamp('created_at', { withTimezone: true }).defaultNow().notNull(),
+    updatedAt: timestamp('updated_at', { withTimezone: true }).defaultNow().notNull(),
+});
+
+export const featureFlagAccess = pgTable('feature_flag_access', {
+    id: serial('id').primaryKey(),
+    flagId: integer('flag_id').notNull().references(() => featureFlags.id, { onDelete: 'cascade' }),
+    guildId: bigint('guild_id', { mode: 'bigint' }),
+    userId: bigint('user_id', { mode: 'bigint' }),
+    roleId: bigint('role_id', { mode: 'bigint' }),
+    createdAt: timestamp('created_at', { withTimezone: true }).defaultNow().notNull(),
+}, (table) => [
+    index('idx_ffa_flag_id').on(table.flagId),
+    index('idx_ffa_guild_id').on(table.guildId),
+    index('idx_ffa_user_id').on(table.userId),
+    index('idx_ffa_role_id').on(table.roleId),
+]);
+
+export const featureFlagsRelations = relations(featureFlags, ({ many }) => ({
+    access: many(featureFlagAccess),
+}));
+
+export const featureFlagAccessRelations = relations(featureFlagAccess, ({ one }) => ({
+    flag: one(featureFlags, {
+        fields: [featureFlagAccess.flagId],
+        references: [featureFlags.id],
+    }),
+}));

shared/db/schema/index.ts

@@ -4,3 +4,4 @@ export * from './inventory';
 export * from './economy';
 export * from './quests';
 export * from './moderation';
+export * from './feature-flags';