Update shared Gaia workflows and Sargo development tooling

Fix camera switching and Contacts/SMS activity routing across shared hosts.
Integrate Marketplace installation and native standalone recovery tools,
Bluetooth runtime packages and trusted certificates.

Update English/French READMEs and the shared changelog with tested scope
and remaining radio/audio/Bluetooth limitations. Preview17 remains the
existing APK; no new native image is released.

Validation: shared JavaScript and native Python tests; Android packaging
and payload parity from an isolated publication checkout.

gaia/apps/marketplace/index.html

@@ -0,0 +1,5 @@
+<!doctype html><html><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1"><title>Marketplace</title><link rel="stylesheet" href="/shared/style/confirm.css"><link rel="stylesheet" href="marketplace.css"><script defer src="marketplace.js"></script></head><body>
+<iframe id="catalogue" mozbrowser title="Marketplace"></iframe>
+<section id="message" hidden><img src="icon.png" alt="" width="96" height="96"><p id="status" role="status"></p><button id="browse" type="button"></button><button id="open" type="button" hidden></button></section>
+<form id="confirm" role="dialog" data-type="confirm" hidden><section><h1 id="title"></h1><p id="question"></p><p id="permissions"></p></section><menu><button id="cancel" type="button"></button><button id="install" type="submit" class="recommend"></button></menu></form>
+</body></html>

gaia/apps/marketplace/manifest.webapp

@@ -0,0 +1,19 @@
+{
+  "name": "Marketplace",
+  "description": "Vulpes OS application catalogue",
+  "launch_path": "/index.html",
+  "type": "certified",
+  "icons": {
+    "512": "/icon.png"
+  },
+  "permissions": {
+    "browser": {},
+    "webapps-manage": {}
+  },
+  "locales": {
+    "fr": {
+      "name": "Marketplace",
+      "description": "Catalogue des applications Vulpes OS"
+    }
+  }
+}

gaia/apps/marketplace/marketplace.css

@@ -0,0 +1 @@
+html,body{width:100%;height:100%;margin:0;background:#f4f4f4;font-family:Fira Sans,sans-serif}#catalogue{position:absolute;inset:0;width:100%;height:100%;border:0}#message{padding:3rem 2rem;text-align:center;font-size:1.8rem}#message button{display:block;width:100%;padding:1rem;margin:1rem 0;font:inherit}#open[hidden],[hidden]{display:none!important}#confirm{z-index:10}#confirm section{overflow:auto}#permissions{font-size:1.5rem}

gaia/apps/marketplace/marketplace.js

@@ -0,0 +1,32 @@
+(async()=>{
+  const frame=document.getElementById('catalogue'),message=document.getElementById('message'),dialog=document.getElementById('confirm');
+  let attempt=0,busy=false,prepared=null,installed=null,language=await VulpesCompat.call('locale.current');
+  const fr=()=>/^fr(?:-|$)/i.test(language);
+  const text=(f,e)=>fr()?f:e;
+  function labels(){document.getElementById('browse').textContent=text('Ouvrir le catalogue','Open catalogue');document.getElementById('open').textContent=text('Ouvrir','Open');document.getElementById('install').textContent=text('Installer','Install');document.getElementById('cancel').textContent=text('Annuler','Cancel');}
+  function loadFailed(){status(text('Catalogue inaccessible. Vérifiez la connexion Internet, puis réessayez.','Catalogue unavailable. Check your Internet connection, then try again.'));document.getElementById('open').hidden=true;}
+  frame.addEventListener('mozbrowsererror',loadFailed);
+  function browse(){labels();message.hidden=true;dialog.hidden=true;frame.style.visibility='visible';frame.src='https://vulpes-os.org/marketplace/?mode=app&lang='+(fr()?'fr':'en');}
+  function status(value){frame.style.visibility='hidden';message.hidden=false;document.getElementById('status').textContent=value;}
+  async function prepare(url){
+    if(busy)return;const current=++attempt;busy=true;prepared=null;installed=null;document.getElementById('open').hidden=true;
+    status(text('Vérification de l’application…','Checking application…'));
+    try {const value=await VulpesCompat.call('marketplace.prepare',{url});if(current!==attempt)return;prepared=value;
+      document.getElementById('title').textContent=prepared.name;
+      document.getElementById('question').textContent=text('Installer cette application archivée ?','Install this archived application?')+' ('+(prepared.bytes/1048576).toFixed(1)+' Mio)';
+      document.getElementById('permissions').textContent=text('Elle sera exécutée comme une application web, sans accès aux fonctions système. Certains anciens services peuvent ne plus fonctionner.','It will run as a web application without system access. Some old services may no longer work.');
+      message.hidden=true;dialog.hidden=false;
+    }catch(error){if(current!==attempt)return;status(text('Installation impossible : ','Cannot install: ')+error.message);busy=false;}
+  }
+  dialog.addEventListener('submit',async event=>{event.preventDefault();if(!prepared)return;const token=prepared.token;prepared=null;dialog.hidden=true;status(text('Installation…','Installing…'));
+    try {installed=await VulpesCompat.call('marketplace.install',{token});status(text('Application ajoutée à l’accueil.','Application added to Home.'));document.getElementById('open').hidden=false;}
+    catch(error){status(text('Installation impossible : ','Cannot install: ')+error.message);}finally{busy=false;}
+  });
+  const cancel=()=>{attempt++;prepared=null;busy=false;VulpesCompat.call('marketplace.cancel').catch(console.error);browse();};
+  document.getElementById('cancel').onclick=cancel;
+  document.getElementById('browse').onclick=cancel;
+  document.getElementById('open').onclick=()=>installed && VulpesCompat.call('apps.launch',{manifestURL:installed.manifestURL});
+  addEventListener('languagechange',()=>{language=navigator.language;if(!busy)browse();});
+  browse();
+  setInterval(async()=>{if(busy)return;try{const url=await VulpesCompat.call('marketplace.poll');if(url)await prepare(url);}catch(error){console.error(error);}},750);
+})();