Add Chromium plugin for Chrome/Edge DOM inspection

[asklar]

Summary

Adds a browser extension + native messaging host architecture that lets lvt dump the DOM tree from Chrome and Edge tabs.

Components

• Browser extension (Manifest V3) — uses chrome.debugger API (CDP) to walk the DOM tree, including shadow DOM. Works on both Chrome and Edge.
• Native messaging host (lvt_chromium_host.exe) — relays between Chrome's stdin/stdout native messaging protocol and a Win32 named pipe
• Plugin DLL (lvt_chromium_plugin.dll) — standard 4-export lvt plugin that detects chrome.exe/msedge.exe and connects to the pipe to request DOM trees
• Deterministic extension ID via fixed key field in manifest — no hardcoded IDs that change per install

Data flow

lvt.exe → plugin DLL → named pipe → host.exe → stdin/stdout → extension → chrome.debugger (CDP) → DOM

No --remote-debugging-port flag required.

One-time setup

1. lvt_chromium_host.exe --register (creates registry entries for Chrome + Edge)
2. Load the extension in Chrome/Edge via chrome://extensions → Load unpacked

Files

File	Purpose
src/plugin_chromium/lvt_chromium_plugin.cpp	Plugin DLL
src/plugin_chromium/chromium_host.cpp	Native messaging host relay
src/plugin_chromium/extension/	Browser extension (manifest + service worker)
docs/chromium-plugin.md	Documentation
tests/chromium_tests.cpp	Unit tests (11 tests)

Pipeline changes

• CI and release pipelines now run lvt_chromium_tests.exe
• Plugins already bundle in the release zip (no changes needed)
• SKILL.md updated with Chromium framework + setup instructions

Tested

Verified end-to-end with Edge Stable on example.com — full DOM tree with tags, text, attributes, and bounding boxes.