feat(logging-p0): add screenshot capture and browser console diagnostics for ERP errors

Enhance ERP automation error diagnostics by capturing PNG screenshots
on every error and forwarding browser console warnings/errors to the
structured logger. Includes automatic cleanup of old screenshots
aligned with the configured log retention period.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/main/services/erp/erp-auth.ts

@@ -2,6 +2,7 @@ import { chromium } from 'playwright'
 import type { ErpConfig, ErpSession } from '../../types/erp.types'
 import { createLogger } from '../logger'
 import { capturePageContext } from './erp-error-context'
+import { attachPageDiagnostics, attachContextDiagnostics } from './page-diagnostics'
 
 const log = createLogger('ErpAuthService')
 
@@ -55,6 +56,8 @@ export class ErpAuthService {
     })
 
     const page = await context.newPage()
+    attachPageDiagnostics(page)
+    attachContextDiagnostics(context)
 
     // Navigate to login page (use actual login URL from Python code)
     const loginUrl = `${this.config.url}/yonbip/resources/uap/rbac/login/main/index.html`

src/main/services/erp/erp-error-context.ts

@@ -6,12 +6,61 @@
  */
 
 import type { Page } from 'playwright'
+import fs from 'fs'
+import path from 'path'
+import { getLogDir } from '../logger/shared'
 
 export interface ErpErrorContext {
   pageUrl?: string
   frameHierarchy?: Array<{ name: string; url: string }>
   targetSelector?: string
   step?: string
+  screenshotPath?: string
+}
+
+/**
+ * Sanitize a step name for use as a filename component.
+ * Replaces non-alphanumeric characters with underscores and truncates.
+ */
+function sanitizeForFilename(step: string | undefined): string {
+  if (!step) return 'unknown'
+  return step.replace(/[^a-zA-Z0-9_-]/g, '_').slice(0, 40)
+}
+
+/**
+ * Capture a screenshot of the page for error diagnostics.
+ * Stored as PNG under <logDir>/screenshots/.
+ * Defensive: never throws.
+ */
+async function captureScreenshot(page: Page, step?: string): Promise<string | undefined> {
+  try {
+    if (page.isClosed()) return undefined
+
+    const screenshotDir = path.join(getLogDir(), 'screenshots')
+    fs.mkdirSync(screenshotDir, { recursive: true })
+
+    const now = new Date()
+    const timestamp = [
+      now.getFullYear(),
+      String(now.getMonth() + 1).padStart(2, '0'),
+      String(now.getDate()).padStart(2, '0'),
+      '_',
+      String(now.getHours()).padStart(2, '0'),
+      String(now.getMinutes()).padStart(2, '0'),
+      String(now.getSeconds()).padStart(2, '0')
+    ].join('')
+
+    const filename = `err_${timestamp}_${sanitizeForFilename(step)}.png`
+    const filePath = path.join(screenshotDir, filename)
+
+    const buffer = await page.screenshot({ type: 'png', timeout: 5000 })
+    fs.writeFileSync(filePath, buffer)
+
+    return filePath
+  } catch {
+    // screenshot failure must not propagate
+    return undefined
+  }
 }
 
 /**
@@ -49,5 +98,7 @@ export async function capturePageContext(
     ctx.step = step
   }
 
+  ctx.screenshotPath = await captureScreenshot(page, step)
+
   return ctx
 }

src/main/services/erp/page-diagnostics.ts

@@ -0,0 +1,50 @@
+/**
+ * Page Diagnostics
+ *
+ * Attaches browser console and error listeners to Playwright pages
+ * so that ERP-side JS errors are visible in the application log.
+ *
+ * Only warning and error level console messages are captured —
+ * ERP (YonBIP) outputs large volumes of info-level messages that
+ * would drown the log.
+ */
+
+import type { Page, BrowserContext } from 'playwright'
+import { createLogger } from '../logger'
+
+const log = createLogger('BrowserDiagnostics')
+
+/**
+ * Attach console and error listeners to a single page.
+ */
+export function attachPageDiagnostics(page: Page): void {
+  page.on('console', (msg) => {
+    const type = msg.type()
+    if (type !== 'warning' && type !== 'error') return
+
+    const location = msg.location()
+    log.error(`[Browser ${type}] ${msg.text()}`, {
+      pageUrl: page.url(),
+      consoleType: type,
+      location: location ? `${location.url}:${location.lineNumber}` : undefined
+    })
+  })
+
+  page.on('pageerror', (error) => {
+    log.error(`[Browser pageerror] ${error.message}`, {
+      pageUrl: page.url(),
+      error: error.message,
+      stack: error.stack
+    })
+  })
+}
+
+/**
+ * Attach diagnostics to all current and future pages in a browser context.
+ * Covers popups and pages opened by ERP automation.
+ */
+export function attachContextDiagnostics(context: BrowserContext): void {
+  context.on('page', (page) => {
+    attachPageDiagnostics(page)
+  })
+}