refactor(bilinovel): Migrate browser automation from Chromedp to Playwright

This commit replaces the `chromedp` library with `playwright-go` for browser automation within the Bilinovel downloader.

Changes include:
*   Updated `Bilinovel` struct to manage Playwright browser, context, and page instances.
*   Rewrote `initBrowser` and `Close` methods to use Playwright's API for browser lifecycle management.
*   Refactored `processContentWithChromedp` to `processContentWithPlaywright`, adapting the logic to use Playwright's page evaluation capabilities.
*   Removed unused `context` and `time` imports.
*   Added HTML cleanup in `getChapterByPage` to remove `class` attributes from images and `data-k` attributes from all elements, improving content consistency.

main.go

@@ -2,8 +2,20 @@ package main
 
 import (
 	"bilinovel-downloader/cmd"
+	"io"
+	"log"
+
+	"github.com/playwright-community/playwright-go"
 )
 
 func main() {
+	log.Println("Installing playwright")
+	err := playwright.Install(&playwright.RunOptions{
+		Browsers: []string{"chromium"},
+		Stdout:   io.Discard,
+	})
+	if err != nil {
+		log.Panicf("failed to install playwright")
+	}
 	_ = cmd.RootCmd.Execute()
 }