chore(release): bump version to v2026.4.113 and revert iframe to webview}
- Bump version from v2026.4.112 to v2026.4.113 in package.json and all docs - Add v2026.4.113 changelog entry - Replace iframe element with webview tag in index.html - Remove WebviewProxy class and getIframeFrame helper from load.mjs - Enable webviewTag and nodeIntegrationInSubFrames in window options - Move Accept-Language header override to did-attach-webview handler - Remove X-Frame-Options/CSP header stripping (no longer needed with webview) - Handle new-window via webview's setWindowOpenHandler instead of parent - Refactor dark mode invert injection to use webview webContents frames - Update navigation event handling to use webview's native events