Implement libinput device configuration

We need to defer config application to the first manage_start event
using a should_manage flag so that all *_support events have arrived
before we try applying the configs

This commit also has two other fixes
- fixes a potential use-after-free by telling InputDevice when a
 LibinputDevice is .removed.
- fix logFn (removed "if (scope != .default) return;")

I used kwm to help figure out the manage pattern for the input config.
Link to kwm: https://github.com/kewuaa/kwm

src/Context.zig

@@ -112,6 +112,12 @@ pub fn manage(context: *Context) void {
         context.config = new_config;
         context.initialized = false;
 
+        // Mark all libinput devices as needing config re-application
+        var dev_it = context.im.libinput_devices.iterator(.forward);
+        while (dev_it.next()) |libinput_device| {
+            libinput_device.should_manage = true;
+        }
+
         if (wallpaper_changed) {
             if (context.wallpaper_image) |img| img.destroy();
             context.wallpaper_image = loadWallpaperImage(new_config);
@@ -132,6 +138,12 @@ pub fn manage(context: *Context) void {
             }
         }
     }
+
+    // Apply input configs for new or reconfigured devices
+    var dev_it = context.im.libinput_devices.iterator(.forward);
+    while (dev_it.next()) |libinput_device| {
+        libinput_device.manage();
+    }
 }
 
 fn loadWallpaperImage(config: *Config) ?*WallpaperImage {