chore(clippy): enable and fix many stricter lints (#3783)

* chore(clippy): enable and fix many stricter lints

These ensure that the codebase uses more idiomatic, performant, and
concise language constructions.

* chore: make non-Clippy compiler warnings also deny by default

packages/app-lib/src/api/pack/install_from.rs

@@ -357,9 +357,7 @@ pub async fn set_profile_information(
         }
     }
 
-    let game_version = if let Some(game_version) = game_version {
-        game_version
-    } else {
+    let Some(game_version) = game_version else {
         return Err(crate::ErrorKind::InputError(
             "Pack did not specify Minecraft version".to_string(),
         )
@@ -393,10 +391,7 @@ pub async fn set_profile_information(
                     locked: if !ignore_lock {
                         true
                     } else {
-                        prof.linked_data
-                            .as_ref()
-                            .map(|x| x.locked)
-                            .unwrap_or(true)
+                        prof.linked_data.as_ref().is_none_or(|x| x.locked)
                     },
                 })
             }