smart truncation, iframe preservation, streamlit filter

- simphtml: truncate_biggest replaces naive string cut, targets fattest content block via 70% drill-down
- simphtml: iframe children preserved through div proxy (bypass BS4 limitation)
- background/content.js: filter streamlit tabs and skip content script injection
- ga.py: file_content tag regex allows attributes; maxchars 38k->35k

assets/tmwd_cdp_bridge/background.js

@@ -341,7 +341,7 @@ chrome.runtime.onInstalled.addListener(() => connectWS());
 // Sync tab list on changes
 async function sendTabsUpdate() {
   if (!ws || ws.readyState !== WebSocket.OPEN) return;
-  const tabs = (await chrome.tabs.query({})).filter(t => isScriptable(t.url));
+  const tabs = (await chrome.tabs.query({})).filter(t => isScriptable(t.url) && !/streamlit/i.test(t.title));
   ws.send(JSON.stringify({
     type: 'tabs_update',
     tabs: tabs.map(t => ({ id: t.id, url: t.url, title: t.title }))