Parse User Agents on the backend side (#2388)

* Parse user agents on the server side

* Parse and expose user agents on the backend

* Use the parsed user agent in the device consent page

* Fix the device icon tests

* Fix clippy warnings

* Box stuff to avoid large enum variants

* Ignore a clippy warning

* Fix the requester boxing

crates/data-model/examples/ua-parser.rs

@@ -0,0 +1,26 @@
+// Copyright 2024 The Matrix.org Foundation C.I.C.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use mas_data_model::UserAgent;
+
+/// Simple command-line tool to try out user-agent parsing
+///
+/// It parses user-agents from stdin and prints the parsed user-agent to stdout.
+fn main() {
+    for line in std::io::stdin().lines() {
+        let user_agent = line.unwrap();
+        let user_agent = UserAgent::parse(user_agent);
+        println!("{user_agent:?}");
+    }
+}