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-a-agent.test.ts

@@ -1,4 +1,5 @@
 import { browser, expect } from '@wdio/globals';
+import { exec } from '../helpers/execute.ts';
 
 // Phase A — Agent: Agent pane initial state + prompt submission + NEW agent tests.
 // Shares a single Tauri app session with other phase-a-* spec files.
@@ -8,7 +9,7 @@ import { browser, expect } from '@wdio/globals';
 async function waitForAgentStatus(status: string, timeout = 30_000): Promise<void> {
   await browser.waitUntil(
     async () => {
-      const attr = await browser.execute(() => {
+      const attr = await exec(() => {
         const el = document.querySelector('[data-testid="agent-pane"]');
         return el?.getAttribute('data-agent-status') ?? 'idle';
       });
@@ -29,18 +30,18 @@ async function sendAgentPrompt(text: string): Promise<void> {
   await textarea.setValue(text);
   await browser.pause(200);
   const submitBtn = await browser.$('[data-testid="agent-submit"]');
-  await browser.execute((el) => (el as HTMLElement).click(), submitBtn);
+  await submitBtn.click();
 }
 
 async function getAgentStatus(): Promise<string> {
-  return browser.execute(() => {
+  return exec(() => {
     const el = document.querySelector('[data-testid="agent-pane"]');
     return el?.getAttribute('data-agent-status') ?? 'unknown';
   });
 }
 
 async function getMessageCount(): Promise<number> {
-  return browser.execute(() => {
+  return exec(() => {
     const area = document.querySelector('[data-testid="agent-messages"]');
     return area ? area.children.length : 0;
   });
@@ -51,7 +52,7 @@ async function getMessageCount(): Promise<number> {
 describe('Scenario 3 — Agent Pane Initial State', () => {
   it('should display agent pane in idle status', async () => {
     if (!(await agentPaneExists())) {
-      await browser.execute(() => {
+      await exec(() => {
         const tab = document.querySelector('[data-testid="project-tabs"] .ptab');
         if (tab) (tab as HTMLElement).click();
       });
@@ -75,7 +76,7 @@ describe('Scenario 3 — Agent Pane Initial State', () => {
   it('should have empty messages area initially', async () => {
     const msgArea = await browser.$('[data-testid="agent-messages"]');
     await expect(msgArea).toBeExisting();
-    const msgCount = await browser.execute(() => {
+    const msgCount = await exec(() => {
       const area = document.querySelector('[data-testid="agent-messages"]');
       return area ? area.querySelectorAll('.message').length : 0;
     });
@@ -83,7 +84,7 @@ describe('Scenario 3 — Agent Pane Initial State', () => {
   });
 
   it('should show agent provider name or badge', async () => {
-    const hasContent = await browser.execute(() => {
+    const hasContent = await exec(() => {
       const session = document.querySelector('[data-testid="agent-session"]');
       return session !== null && (session.textContent ?? '').length > 0;
     });
@@ -93,7 +94,7 @@ describe('Scenario 3 — Agent Pane Initial State', () => {
   it('should show cost display area (when session exists) or prompt area', async () => {
     // status-strip only renders when session is non-null; before first query
     // the agent pane shows only the prompt area — both are valid states
-    const state = await browser.execute(() => {
+    const state = await exec(() => {
       const pane = document.querySelector('[data-testid="agent-pane"]');
       if (!pane) return 'no-pane';
       if (pane.querySelector('.status-strip')) return 'has-status';
@@ -106,7 +107,7 @@ describe('Scenario 3 — Agent Pane Initial State', () => {
 
   it('should show agent pane with prompt or status area', async () => {
     // Context meter only visible during running state; verify pane structure instead
-    const hasPane = await browser.execute(() => {
+    const hasPane = await exec(() => {
       const pane = document.querySelector('[data-testid="agent-pane"]');
       return pane !== null;
     });
@@ -114,7 +115,7 @@ describe('Scenario 3 — Agent Pane Initial State', () => {
   });
 
   it('should have tool call/result collapsible sections area', async () => {
-    const ready = await browser.execute(() => {
+    const ready = await exec(() => {
       const area = document.querySelector('[data-testid="agent-messages"]');
       return area !== null && area instanceof HTMLElement;
     });
@@ -138,7 +139,7 @@ describe('Scenario 7 — Agent Prompt Submission', () => {
     const textarea = await browser.$('[data-testid="agent-prompt"]');
     await textarea.setValue('Test prompt');
     await browser.pause(200);
-    const isDisabled = await browser.execute(() => {
+    const isDisabled = await exec(() => {
       const btn = document.querySelector('[data-testid="agent-submit"]');
       return btn ? (btn as HTMLButtonElement).disabled : true;
     });
@@ -204,7 +205,7 @@ describe('Scenario 7 — Agent Prompt Submission', () => {
     try { await waitForAgentStatus('running', 15_000); } catch {
       this.skip(); return;
     }
-    const uiState = await browser.execute(() => {
+    const uiState = await exec(() => {
       const textarea = document.querySelector('[data-testid="agent-prompt"]') as HTMLTextAreaElement | null;
       const stopBtn = document.querySelector('[data-testid="agent-stop"]');
       return {
@@ -214,7 +215,7 @@ describe('Scenario 7 — Agent Prompt Submission', () => {
     });
     expect(uiState.textareaDisabled || uiState.stopBtnVisible).toBe(true);
     try { await waitForAgentStatus('idle', 40_000); } catch {
-      await browser.execute(() => {
+      await exec(() => {
         const btn = document.querySelector('[data-testid="agent-stop"]');
         if (btn) (btn as HTMLElement).click();
       });