refactor: extract DebugHelper from ComfyPage.ts

- Create browser_tests/fixtures/helpers/DebugHelper.ts with 7 methods

- Add debug: DebugHelper property to ComfyPage

- Replace debug methods with deprecation proxies delegating to this.debug

- Reduces ComfyPage.ts by ~140 lines

Amp-Thread-ID: https://ampcode.com/threads/T-019c1206-3625-71ef-b976-1796574b9642
Co-authored-by: Amp <amp@ampcode.com>

browser_tests/fixtures/helpers/DebugHelper.ts

@@ -0,0 +1,167 @@
+import type { Locator, Page, TestInfo } from '@playwright/test'
+
+import type { Position } from '../types'
+
+export interface DebugScreenshotOptions {
+  fullPage?: boolean
+  element?: 'canvas' | 'page'
+  markers?: Array<{ position: Position; id?: string }>
+}
+
+export class DebugHelper {
+  constructor(
+    private page: Page,
+    private canvas: Locator
+  ) {}
+
+  async addMarker(
+    position: Position,
+    id: string = 'debug-marker'
+  ): Promise<void> {
+    await this.page.evaluate(
+      ([pos, markerId]) => {
+        const existing = document.getElementById(markerId)
+        if (existing) existing.remove()
+
+        const marker = document.createElement('div')
+        marker.id = markerId
+        marker.style.position = 'fixed'
+        marker.style.left = `${pos.x - 10}px`
+        marker.style.top = `${pos.y - 10}px`
+        marker.style.width = '20px'
+        marker.style.height = '20px'
+        marker.style.border = '2px solid red'
+        marker.style.borderRadius = '50%'
+        marker.style.backgroundColor = 'rgba(255, 0, 0, 0.3)'
+        marker.style.pointerEvents = 'none'
+        marker.style.zIndex = '10000'
+        document.body.appendChild(marker)
+      },
+      [position, id] as const
+    )
+  }
+
+  async removeMarkers(): Promise<void> {
+    await this.page.evaluate(() => {
+      document
+        .querySelectorAll('[id^="debug-marker"]')
+        .forEach((el) => el.remove())
+    })
+  }
+
+  async attachScreenshot(
+    testInfo: TestInfo,
+    name: string,
+    options?: DebugScreenshotOptions
+  ): Promise<void> {
+    if (options?.markers) {
+      for (const marker of options.markers) {
+        await this.addMarker(marker.position, marker.id)
+      }
+    }
+
+    let screenshot: Buffer
+    const targetElement = options?.element || 'page'
+
+    if (targetElement === 'canvas') {
+      screenshot = await this.canvas.screenshot()
+    } else if (options?.fullPage) {
+      screenshot = await this.page.screenshot({ fullPage: true })
+    } else {
+      screenshot = await this.page.screenshot()
+    }
+
+    await testInfo.attach(name, {
+      body: screenshot,
+      contentType: 'image/png'
+    })
+
+    if (options?.markers) {
+      await this.removeMarkers()
+    }
+  }
+
+  async saveCanvasScreenshot(filename: string): Promise<void> {
+    await this.page.evaluate(async (filename) => {
+      const canvas = document.getElementById(
+        'graph-canvas'
+      ) as HTMLCanvasElement
+      if (!canvas) {
+        throw new Error('Canvas not found')
+      }
+
+      return new Promise<void>((resolve) => {
+        canvas.toBlob(async (blob) => {
+          if (!blob) {
+            throw new Error('Failed to create blob from canvas')
+          }
+
+          const url = URL.createObjectURL(blob)
+          const a = document.createElement('a')
+          a.href = url
+          a.download = filename
+          document.body.appendChild(a)
+          a.click()
+          document.body.removeChild(a)
+          URL.revokeObjectURL(url)
+          resolve()
+        }, 'image/png')
+      })
+    }, filename)
+  }
+
+  async getCanvasDataURL(): Promise<string> {
+    return await this.page.evaluate(() => {
+      const canvas = document.getElementById(
+        'graph-canvas'
+      ) as HTMLCanvasElement
+      if (!canvas) {
+        throw new Error('Canvas not found')
+      }
+      return canvas.toDataURL('image/png')
+    })
+  }
+
+  async showCanvasOverlay(): Promise<void> {
+    await this.page.evaluate(() => {
+      const canvas = document.getElementById(
+        'graph-canvas'
+      ) as HTMLCanvasElement
+      if (!canvas) {
+        throw new Error('Canvas not found')
+      }
+
+      const existingOverlay = document.getElementById('debug-canvas-overlay')
+      if (existingOverlay) {
+        existingOverlay.remove()
+      }
+
+      const overlay = document.createElement('div')
+      overlay.id = 'debug-canvas-overlay'
+      overlay.style.position = 'fixed'
+      overlay.style.top = '0'
+      overlay.style.left = '0'
+      overlay.style.zIndex = '9999'
+      overlay.style.backgroundColor = 'white'
+      overlay.style.padding = '10px'
+      overlay.style.border = '2px solid red'
+
+      const img = document.createElement('img')
+      img.src = canvas.toDataURL('image/png')
+      img.style.maxWidth = '800px'
+      img.style.maxHeight = '600px'
+      overlay.appendChild(img)
+
+      document.body.appendChild(overlay)
+    })
+  }
+
+  async hideCanvasOverlay(): Promise<void> {
+    await this.page.evaluate(() => {
+      const overlay = document.getElementById('debug-canvas-overlay')
+      if (overlay) {
+        overlay.remove()
+      }
+    })
+  }
+}