feat: Phase 9 — Web client SPA with WebRTC P2P transport

Complete browser-based client: Preact SPA with login, group file browser,
encrypted download, video playback, group chat, i18n, and dark/light theme.
Browser connects P2P to nodes behind residential NAT via WebRTC DataChannel
(aiortc). Hub handles signaling only — all data flows E2E.

Performance: pipelined downloads (8-chunk sliding window), binary msgpack
wire format (no base64), redundant I/O elimination. Large file downloads
stream to disk via File System Access API (showSaveFilePicker).

Validated on SFR + Orange residential NATs, Chrome + Firefox, IPv4/IPv6.
132 tests passing. Deployed to meshbay.org + Orange node.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/api/groups.py b/packages/meshbay-hub/src/meshbay_hub/api/groups.py
index 5bccf71..6dd4275 100644
--- a/packages/meshbay-hub/src/meshbay_hub/api/groups.py
+++ b/packages/meshbay-hub/src/meshbay_hub/api/groups.py
@@ -15,6 +15,57 @@ from meshbay_hub.db.models import (
 router = APIRouter(prefix="/v1/groups", tags=["groups"])
 
 
+@router.get("/mine")
+async def my_groups(
+    current_user: User = Depends(get_current_user),
+    db: AsyncSession = Depends(get_db),
+):
+    """List groups the current user belongs to."""
+    result = await db.execute(
+        select(Group)
+        .join(GroupMember, Group.id == GroupMember.group_id)
+        .where(GroupMember.user_id == current_user.id, Group.status == "active")
+        .order_by(Group.name)
+    )
+    groups = result.scalars().all()
+    return {
+        "groups": [
+            {
+                "id": g.id,
+                "name": g.name,
+                "visibility": g.visibility,
+                "join_policy": g.join_policy,
+                "created_at": g.created_at.isoformat(),
+                "is_admin": g.admin_id == current_user.id,
+            }
+            for g in groups
+        ]
+    }
+
+
+@router.get("/{group_id}/nodes")
+async def group_online_nodes(
+    group_id: str,
+    current_user: User = Depends(get_current_user),
+    db: AsyncSession = Depends(get_db),
+):
+    """Return online nodes that serve a group (for WebRTC connection)."""
+    from meshbay_hub.api.revocation import get_online_nodes_for_group
+    from meshbay_hub.db.models import Node
+
+    group = await db.get(Group, group_id)
+    if not group:
+        raise HTTPException(status_code=404, detail="Group not found")
+
+    node_ids = get_online_nodes_for_group(group_id)
+    nodes = []
+    for nid in node_ids:
+        node = await db.get(Node, nid)
+        if node:
+            nodes.append({"node_id": nid, "pk_node": node.pk_node})
+    return {"nodes": nodes}
+
+
 @router.get("")
 async def list_public_groups(
     db: AsyncSession = Depends(get_db),