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.

admin-dashboard/src/oauth.ts

@@ -0,0 +1,51 @@
+export interface OAuthUiState {
+  code: string | null;
+  state: string | null;
+  error: string | null;
+}
+
+const STATE_STORAGE_KEY = "omo.dashboard.oauth.state";
+
+export function readOAuthUiState(): OAuthUiState {
+  const params = new URLSearchParams(window.location.search);
+  return {
+    code: params.get("code"),
+    state: params.get("state"),
+    error: params.get("error"),
+  };
+}
+
+export function buildDiscordAuthorizeUrl(
+  clientId: string,
+  redirectUri: string,
+): string {
+  const state = crypto.randomUUID();
+  window.localStorage.setItem(STATE_STORAGE_KEY, state);
+
+  const url = new URL("https://discord.com/oauth2/authorize");
+  url.searchParams.set("client_id", clientId);
+  url.searchParams.set("response_type", "code");
+  url.searchParams.set("scope", "identify guilds");
+  url.searchParams.set("redirect_uri", redirectUri);
+  url.searchParams.set("state", state);
+  url.searchParams.set("prompt", "consent");
+
+  return url.toString();
+}
+
+export function isExpectedOAuthState(state: string | null): boolean {
+  if (!state) {
+    return false;
+  }
+
+  const expected = window.localStorage.getItem(STATE_STORAGE_KEY);
+  return expected === state;
+}
+
+export function clearOAuthQueryParams(): void {
+  const url = new URL(window.location.href);
+  url.searchParams.delete("code");
+  url.searchParams.delete("state");
+  url.searchParams.delete("error");
+  window.history.replaceState({}, document.title, url.toString());
+}