Add account signup and turnstile, subroom perms (#24)

* turnstile

* require turnstile

* homepage refresh

* implemented rooms visited endpoint for friends

* update default profile pic

* add a meta download button

* add subroom permissions

* enable signup

apps/rooms/migrations/0009_subroom_permissions.sql

@@ -0,0 +1,29 @@
+-- Per-subroom permission overrides. `PUT /rooms/{roomId}/subrooms/{subRoomId}/permissions`
+-- is how a room's creator changes what a role may do in one subroom (spawn inventions,
+-- invite, use the delete-all button, …). The client addresses an entry by the
+-- (`Permission`, `Role`) pair and re-PUTs that pair to change it, so the pair is the
+-- primary key: sending it again overwrites the stored row rather than appending a second.
+--
+-- A row IS an override, so the client's `Override` flag is not a column. It's the checkbox
+-- the client draws next to each permission — `Override: true` stores the value, and
+-- `Override: false` means "fall back to the default", which deletes the row. Reads always
+-- serve `Override: true`.
+--
+-- Read on one path only — `GET /photon_access_token`, where a stored entry overwrites the
+-- matching default in the permission table the client applies when it spawns. That's why
+-- this is its own table rather than a field on the subroom's `data` blob: that blob is
+-- served to the client verbatim inside the room, and nothing client-facing reads these.
+--
+-- `value` is the client's string kept verbatim: usually `True`/`False`, but a permission
+-- whose UI isn't a True/False picker carries something else, and we don't interpret it.
+--
+-- Generated from packages/domain/src/rooms-db.ts (SUBROOM_SCHEMA_DDL) — keep in sync.
+
+CREATE TABLE IF NOT EXISTS subroom_permission (
+  sub_room_id INTEGER NOT NULL,
+  permission TEXT NOT NULL,
+  role INTEGER NOT NULL,
+  type INTEGER NOT NULL DEFAULT 0,
+  value TEXT NOT NULL,
+  PRIMARY KEY (sub_room_id, permission, role)
+  );