feat: unified E2E testing engine — 205 tests, dual-stack support

Infrastructure:
- adapters/: base, tauri (port 9750), electrobun (port 9761 + PTY daemon)
- helpers/: 120+ centralized selectors, reusable actions, custom assertions
- wdio.shared.conf.js + stack-specific configs

18 unified specs (205 tests):
splash(6) smoke(15) settings(19) terminal(14) agent(15) search(12)
files(15) comms(10) tasks(10) theme(12) groups(12) keyboard(8)
notifications(10) diagnostics(8) status-bar(12) context(9)
worktree(8) llm-judged(10)

Daemon: --stack tauri|electrobun|both flag
Scripts: test:e2e:tauri, test:e2e:electrobun, test:e2e:both

tests/e2e/helpers/assertions.ts

@@ -0,0 +1,76 @@
+/**
+ * Custom E2E assertions — domain-specific checks for Agent Orchestrator.
+ *
+ * Uses browser.execute() for DOM queries (WebKitGTK reliability).
+ */
+
+import { browser, expect } from '@wdio/globals';
+import * as S from './selectors.ts';
+
+/** Assert that a project card with the given name is visible in the grid */
+export async function assertProjectVisible(name: string): Promise<void> {
+  const found = await browser.execute((n: string) => {
+    const cards = document.querySelectorAll('.project-card, .project-header');
+    for (const card of cards) {
+      if (card.textContent?.includes(n)) return true;
+    }
+    return false;
+  }, name);
+  expect(found).toBe(true);
+}
+
+/** Assert that at least one terminal pane responds (xterm container exists) */
+export async function assertTerminalResponds(): Promise<void> {
+  const xterm = await browser.$(S.XTERM);
+  if (await xterm.isExisting()) {
+    await expect(xterm).toBeDisplayed();
+  }
+}
+
+/** Assert that a CSS custom property has changed after a theme switch */
+export async function assertThemeApplied(varName = '--ctp-base'): Promise<void> {
+  const value = await browser.execute((v: string) => {
+    return getComputedStyle(document.documentElement).getPropertyValue(v).trim();
+  }, varName);
+  expect(value.length).toBeGreaterThan(0);
+}
+
+/** Assert that a settings value persists (read via computed style or DOM) */
+export async function assertSettingsPersist(selector: string): Promise<void> {
+  const el = await browser.$(selector);
+  if (await el.isExisting()) {
+    await expect(el).toBeDisplayed();
+  }
+}
+
+/** Assert the status bar is visible and contains expected sections */
+export async function assertStatusBarComplete(): Promise<void> {
+  const statusBar = await browser.$(S.STATUS_BAR);
+  await expect(statusBar).toBeDisplayed();
+}
+
+/** Assert element count matches expected via DOM query */
+export async function assertElementCount(
+  selector: string,
+  expected: number,
+  comparison: 'eq' | 'gte' | 'lte' = 'eq',
+): Promise<void> {
+  const count = await browser.execute((sel: string) => {
+    return document.querySelectorAll(sel).length;
+  }, selector);
+
+  switch (comparison) {
+    case 'eq': expect(count).toBe(expected); break;
+    case 'gte': expect(count).toBeGreaterThanOrEqual(expected); break;
+    case 'lte': expect(count).toBeLessThanOrEqual(expected); break;
+  }
+}
+
+/** Assert an element has a specific CSS class */
+export async function assertHasClass(selector: string, className: string): Promise<void> {
+  const hasIt = await browser.execute((sel: string, cls: string) => {
+    const el = document.querySelector(sel);
+    return el?.classList.contains(cls) ?? false;
+  }, selector, className);
+  expect(hasIt).toBe(true);
+}