Revert "refactor(nix): nix-filter -> lib.fileset"

This reverts commit 8312713dc2.

See nix#9428. Path coercion like `"${./.}"` in flakes causes the path to
be copied to the store twice; using the `self` argument works around
this. However, as `lib.fileset` doesn't support using `self`, so we need
to go back to `nix-filter`

Signed-off-by: seth <getchoo@tuta.io>

flake.lock

@@ -32,6 +32,21 @@
         "type": "github"
       }
     },
+    "nix-filter": {
+      "locked": {
+        "lastModified": 1710156097,
+        "narHash": "sha256-1Wvk8UP7PXdf8bCCaEoMnOT1qe5/Duqgj+rL8sRQsSM=",
+        "owner": "numtide",
+        "repo": "nix-filter",
+        "rev": "3342559a24e85fc164b295c3444e8a139924675b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "nix-filter",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1723637854,
@@ -52,6 +67,7 @@
       "inputs": {
         "flake-compat": "flake-compat",
         "libnbtplusplus": "libnbtplusplus",
+        "nix-filter": "nix-filter",
         "nixpkgs": "nixpkgs"
       }
     }

flake.nix

@@ -14,6 +14,8 @@
       flake = false;
     };
 
+    nix-filter.url = "github:numtide/nix-filter";
+
     /*
       Inputs below this are optional and can be removed
 
@@ -40,6 +42,7 @@
       self,
       nixpkgs,
       libnbtplusplus,
+      nix-filter,
       ...
     }:
     let
@@ -86,7 +89,14 @@
           version = builtins.substring 0 8 self.lastModifiedDate or "dirty";
         in
         {
-          prismlauncher-unwrapped = prev.callPackage ./nix/unwrapped.nix { inherit libnbtplusplus version; };
+          prismlauncher-unwrapped = prev.callPackage ./nix/unwrapped.nix {
+            inherit
+              libnbtplusplus
+              nix-filter
+              self
+              version
+              ;
+          };
 
           prismlauncher = final.callPackage ./nix/wrapper.nix { };
         };

nix/unwrapped.nix

@@ -10,6 +10,8 @@
   jdk17,
   kdePackages,
   ninja,
+  nix-filter,
+  self,
   stripJavaArchivesHook,
   tomlplusplus,
   zlib,
@@ -27,20 +29,18 @@ stdenv.mkDerivation {
   pname = "prismlauncher-unwrapped";
   inherit version;
 
-  src = lib.fileset.toSource {
-    root = ../.;
-    fileset = lib.fileset.unions (
-      map (fileName: ../${fileName}) [
+  src = nix-filter.lib {
+    root = self;
+    include = [
       "buildconfig"
       "cmake"
       "launcher"
       "libraries"
       "program_info"
       "tests"
-        "COPYING.md"
-        "CMakeLists.txt"
-      ]
-    );
+      ../COPYING.md
+      ../CMakeLists.txt
+    ];
   };
 
   postUnpack = ''