Fix/3187 tvtv us scraper

[Sicilykill]

Description

Fixes the tvtv.us scraper by migrating to the new HTMX-based API and implementing Cloudflare bypass using Playwright.

Problem

The tvtv.us site changed their API structure:

• Old API endpoint (/api/v1/lineup/.../grid/...) returns 404 errors
• Timestamps were incorrectly treated as local time instead of UTC, causing a 4-hour offset for users

Solution

• API Migration: Updated from /api/v1/lineup/.../grid/... to /partial/source/{timestamp}/{channel_id}
• Cloudflare Bypass: Implemented Playwright headless browser adapter in shared location
• Timezone Fix: Changed from dayjs(timestamp) to dayjs.utc(timestamp) to correctly handle UTC times
• Parser Update: Switched from JSON to HTML parsing using cheerio
• Integration: Added automatic Playwright detection in [grab.ts]

Changes

• Updated sites/tvtv.us/tvtv.us.config.js New API endpoint, fixed timestamps, HTML parser
• Created scripts/helpers/playwright-adapter.js Shared Playwright adapter (reusable by other sites if needed)
• Updated sites/tvtv.us/tvtv.us.test.js Tests for new HTML structure
• Created sites/tvtv.us/README.md Documentation for the scraper
• Modified scripts/commands/epg/grab.ts Auto-loads Playwright for sites that need it
• Updated SITES.md Marked tvtv.us as working (🟢)
• Updated package.json Added playwright dependency

Additional Notes

The Playwright adapter is generic and reusable for any site requiring Cloudflare bypass. It's in a shared location (scripts/helpers/playwright-adapter.js) so other scrapers can easily use it by:

1. Adding to the sitesNeedingPlaywright array in [grab.ts]
2. Using adapter: playwrightAdapter in their site config

Setup Requirements

After merging, users will need to install Chromium browser binaries. I guess we could add this as a post script? Not sure on how this should be handled.

npm install
npx playwright install chromium

Fixes issues #3187 and partially #3147