Use Nix flake for devShell, create Nix package

Signed-off-by: Humaid Alqasimi <humaid.alqassimi@tii.ae>

.envrc

@@ -0,0 +1,4 @@
+if ! has nix_direnv_version || ! nix_direnv_version 3.0.5; then
+    source_url "https://raw.githubusercontent.com/nix-community/nix-direnv/3.0.5/direnvrc" "sha256-RuwIS+QKFj/T9M2TFXScjBsLR6V3A17YVoEW/Q6AZ1w="
+fi
+use flake

.gitignore

@@ -1 +1,3 @@
 target
+.direnv/
+result

flake.nix

@@ -0,0 +1,57 @@
+{
+  description = "Nix Flake for Ghaf Control Panel";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+  inputs.flake-utils.url = "github:numtide/flake-utils";
+
+  outputs = {
+    nixpkgs,
+    flake-utils,
+    ...
+  }:
+    flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = nixpkgs.legacyPackages.${system};
+    in rec {
+      devShells.default = pkgs.mkShell {
+        packages = [
+          pkgs.bashInteractive
+
+          pkgs.glib
+          pkgs.gtk4
+          pkgs.libadwaita
+          pkgs.pkg-config
+          pkgs.gcc
+          pkgs.rustc
+          pkgs.cargo
+          pkgs.protoc-gen-tonic
+          pkgs.protobuf
+        ];
+        PKG_CONFIG_PATH = "${pkgs.glib.dev}/lib/pkgconfig:${pkgs.gtk4.dev}/lib/pkgconfig";
+      };
+
+      packages.ghaf-ctrl-panel = pkgs.rustPlatform.buildRustPackage {
+        pname = "ghaf-ctrl-panel";
+        version = "0.1.0";
+
+        buildInputs = with pkgs; [
+          gtk4
+          glib
+          libadwaita
+        ];
+
+        nativeBuildInputs = with pkgs; [
+          gtk4
+          glib
+          rustPlatform.cargoSetupHook
+          rustc
+          cargo
+          pkg-config
+          protoc-gen-tonic
+          protobuf
+        ];
+        cargoHash = "sha256-fjmEzXUyCoEiQiuQDA1195kLSmhTCcDSGZKj9quuNFA=";
+
+        src = ./.;
+      };
+      defaultPackage = packages.ghaf-ctrl-panel;
+    });
+}