fix(e2e): cross-protocol browser.execute() — works with both WebDriver + CDP

Root cause: WebDriverIO devtools protocol wraps functions in a polyfill
that puts `return` inside eval() (not a function body) → "Illegal return".

Fix: exec() wrapper in helpers/execute.ts converts function args to IIFE
strings before passing to browser.execute(). Works identically on both
WebDriver (Tauri) and CDP/devtools (Electrobun CEF).

- 35 spec files updated (browser.execute → exec)
- 4 config files updated (string-form expressions)
- helpers/actions.ts + assertions.ts updated
- 560 vitest + 116 cargo passing

tests/e2e/specs/phase-c-llm.test.ts

@@ -1,5 +1,6 @@
 import { browser, expect } from '@wdio/globals';
 import { isJudgeAvailable, assertWithJudge } from '../infra/llm-judge';
+import { exec } from '../helpers/execute.ts';
 
 // Phase C — LLM-Judged Tests (C10-C11)
 // Settings completeness and status bar completeness via LLM judge.
@@ -15,13 +16,13 @@ describe('Scenario C10 — LLM-Judged Settings Completeness', () => {
     }
 
     // Open settings
-    await browser.execute(() => {
+    await exec(() => {
       const btn = document.querySelector('[data-testid="settings-btn"]');
       if (btn) (btn as HTMLElement).click();
     });
     await browser.pause(500);
 
-    const settingsContent = await browser.execute(() => {
+    const settingsContent = await exec(() => {
       const panel = document.querySelector('.sidebar-panel .settings-panel');
       return panel?.textContent ?? '';
     });
@@ -37,7 +38,7 @@ describe('Scenario C10 — LLM-Judged Settings Completeness', () => {
       console.log(`LLM Judge: ${verdict.reasoning} (confidence: ${verdict.confidence})`);
     }
 
-    await browser.execute(() => {
+    await exec(() => {
       const btn = document.querySelector('.panel-close');
       if (btn) (btn as HTMLElement).click();
     });
@@ -55,12 +56,12 @@ describe('Scenario C11 — LLM-Judged Status Bar Completeness', () => {
       return;
     }
 
-    const statusBarContent = await browser.execute(() => {
+    const statusBarContent = await exec(() => {
       const bar = document.querySelector('[data-testid="status-bar"]');
       return bar?.textContent ?? '';
     });
 
-    const statusBarHtml = await browser.execute(() => {
+    const statusBarHtml = await exec(() => {
       const bar = document.querySelector('[data-testid="status-bar"]');
       return bar?.innerHTML ?? '';
     });