Show desktop notification for low RLIMIT_RTTIME

For the same reason as the last commit, since people otherwise just miss
this.

CHANGELOG.md

@@ -15,6 +15,12 @@ Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### Added
 
+- Yabridge will now also show desktop notifications when encountering low
+  `RLIMIT_RTTIME` and `RLIMIT_MEMLOCK` values. This can happen on systems that
+  have not yet been configured correctly for pro audio work, and certain plugins
+  will crash during initialization until this is fixed. We would already print
+  warnings about this to the terminal, but since some don't read those it seems
+  like a good idea to make them more visible.
 - Added a new `editor_coordinate_hack` option which replaces
   `editor_double_embed`. This can be useful with buggy plugins that have their
   editor GUIs misaligned after resizing the window because they draw their GUI

src/plugin/bridges/common.h

@@ -159,8 +159,23 @@ class PluginBridge {
                     init_msg << "   using PipeWire. yabridge may crash when "
                                 "loading plugins"
                              << std::endl;
-                    init_msg << "   until you fix this." << std::endl;
+                    init_msg << "   until you fix this. Check the readme for "
+                                "instructions"
+                             << std::endl;
+                    init_msg << "   on how to fix this." << std::endl;
                     init_msg << std::endl;
+
+                    send_notification(
+                        "Low RTTIME limit detected",
+                        "RLIMIT_RTTIME is set to " +
+                            std::to_string(*rttime_limit) +
+                            " us. This can happen when using PipeWire's JACK "
+                            "backend with the default settings. Some plugins "
+                            "may crash during initialization because of this, "
+                            "so it's recommended to either increase or to "
+                            "remove this limit. Check the readme for "
+                            "instructions on how to do that.",
+                        false);
                 } else {
                     init_msg << "'yes'" << std::endl;
                 }