feat: Implement Tour Schedule Engine with queue management and announcement features

- Added TourScheduleEngine class for managing user queues in a guild.
- Implemented methods for joining, leaving, listing, and clearing queues.
- Added functionality to promote users to speaker in a stage channel and send announcements.
- Created integration tests for the TourScheduleEngine to verify FIFO behavior and announcement dispatch.

test: Add unit tests for ping and sign-up commands

- Created tests for ping command to ensure it replies with "Pong!".
- Implemented tests for sign-up command to verify queue joining, listing, and permission checks.

test: Add integration tests for mileage engine flow

- Developed tests to validate mileage awarding, event persistence, and role upgrades based on mileage thresholds.

chore: Update TypeScript configuration for ESLint

- Added tsconfig.eslint.json for ESLint integration.
- Modified tsconfig.json to exclude test files from the main compilation.

.env.example

@@ -1,4 +1,14 @@
-DISCORD_TOKEN=
-DISCORD_CLIENT_ID=
-# Optional. If set, command registration targets this guild for instant updates.
+# Bootstrap environment variables.
+# Runtime configuration is loaded from bot_settings in Config DB.
+# Keep only database bootstrap values in .env.
+DATABASE_URL=postgres://postgres:postgres@localhost:5432/omo_bot
+CONFIG_DB_ENABLED=true
+
+# Optional scope used by db:seed for guild-specific keys.
+# If omitted, seed writes to __global__ scope.
 DISCORD_GUILD_ID=
+
+# One-time migration path (legacy env -> Config DB):
+# 1) Temporarily set legacy env keys.
+# 2) Run npm run db:seed.
+# 3) Remove legacy env keys from .env.