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.

tundra/tools/restore-standalone-sargo.py

@@ -0,0 +1,83 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: MPL-2.0
+"""Restore a private full-storage backup after a standalone Sargo test.
+
+Default: verify the archive and partition backups only. --restore overwrites
+userdata and the three slot-A boot partitions. Backups are device-specific.
+"""
+import argparse
+import gzip
+import hashlib
+import json
+from pathlib import Path
+import shutil
+import subprocess
+
+
+def digest(path):
+    sha=hashlib.sha256()
+    with path.open('rb') as source:
+        while block:=source.read(4*1024**2):sha.update(block)
+    return sha.hexdigest()
+
+
+def main():
+    parser=argparse.ArgumentParser(description=__doc__)
+    parser.add_argument('--backup',required=True,type=Path)
+    parser.add_argument('--restore',action='store_true')
+    args=parser.parse_args();folder=args.backup.resolve()
+    manifest=json.loads((folder/'recovery.json').read_text())
+    if manifest.get('device')!='sargo' or manifest.get('activeSlot')!='a':raise ValueError('Wrong recovery target')
+    data=json.loads((folder/'userdata.json').read_text())
+    if not data.get('checked') or data.get('archive')!='userdata-original.raw.gz':raise ValueError('Unverified userdata backup')
+    if not data.get('sourceWasUnmounted') or manifest.get('userdataSha256')!=data['sha256'] or manifest.get('userdataBytes')!=data['bytes']:
+        raise ValueError('Storage backup is not bound to this recovery kit')
+    for name,record in manifest['files'].items():
+        if name not in ('boot_a.img','dtbo_a.img','vbmeta_a.img'):raise ValueError('Unexpected recovery partition')
+        path=folder/name
+        if path.is_symlink() or path.stat().st_size!=record['bytes'] or digest(path)!=record['sha256']:raise ValueError('Partition backup changed: '+name)
+    if set(manifest['files'])!={'boot_a.img','dtbo_a.img','vbmeta_a.img'}:raise ValueError('Incomplete boot backup set')
+    archive=folder/data['archive'];sha=hashlib.sha256();count=0
+    with gzip.open(archive,'rb') as source:
+        while block:=source.read(4*1024**2):
+            count+=len(block)
+            if count>data['bytes']:raise ValueError('Oversized backup')
+            sha.update(block)
+    if count!=data['bytes'] or sha.hexdigest()!=data['sha256']:raise ValueError('Storage backup changed')
+    print('Private boot and full userdata backups verified.')
+    if not args.restore:
+        print('No phone action. --restore replaces its current userdata.');return
+    fastboot=shutil.which('fastboot')
+    if not fastboot:raise ValueError('Fastboot is required')
+    serials=[line.split()[0] for line in subprocess.check_output([fastboot,'devices'],text=True).splitlines() if len(line.split())==2]
+    matches=[serial for serial in serials if hashlib.sha256(serial.encode()).hexdigest()==manifest['serialSha256']]
+    if len(matches)!=1:raise ValueError('Original phone not present in Fastboot')
+    serial=matches[0]
+    # Use the standalone installer's strict Fastboot variable parser.
+    import importlib.util
+    spec=importlib.util.spec_from_file_location('flash',Path(__file__).with_name('flash-standalone-sargo.py'))
+    flash=importlib.util.module_from_spec(spec);spec.loader.exec_module(flash)
+    if flash.getvar(fastboot,serial,'product')!='sargo' or flash.getvar(fastboot,serial,'unlocked')!='yes':raise ValueError('Wrong or locked phone')
+    if int(flash.getvar(fastboot,serial,'partition-size:userdata'),16)!=data['bytes']:raise ValueError('Storage geometry changed')
+    raw=folder/'userdata-restore.raw'
+    if raw.exists():
+        if raw.stat().st_size!=data['bytes'] or digest(raw)!=data['sha256']:raise ValueError('Existing restoration file changed')
+    else:
+        if shutil.disk_usage(folder).free<data['bytes']+1024**3:raise ValueError('Not enough host space to decompress recovery image')
+        partial=folder/'userdata-restore.partial'
+        with gzip.open(archive,'rb') as source,partial.open('xb') as target:
+            while block:=source.read(4*1024**2):
+                if not block.strip(b'\0'):target.seek(len(block),1)
+                else:target.write(block)
+            target.truncate(data['bytes'])
+        if digest(partial)!=data['sha256']:raise ValueError('Decompressed backup changed')
+        partial.rename(raw)
+    subprocess.run([fastboot,'-s',serial,'erase','userdata'],check=True,timeout=300)
+    subprocess.run([fastboot,'-s',serial,'-S','256M','flash','userdata',str(raw)],check=True,timeout=7200)
+    for name in ('dtbo_a.img','vbmeta_a.img','boot_a.img'):
+        subprocess.run([fastboot,'-s',serial,'flash',name.removesuffix('.img'),str(folder/name)],check=True,timeout=120)
+    subprocess.run([fastboot,'-s',serial,'set_active','a'],check=True,timeout=30)
+    print('Original userdata and boot restored. Select Start; bootloader remains unlocked.')
+
+
+if __name__=='__main__':main()