use deployed environment for launching nixops4 from the panel

this still needs more work to clean up fully

panel/env.nix

@@ -9,10 +9,4 @@ in
 {
   REPO_DIR = toString ../.;
   # explicitly use nix, as e.g. lix does not have configurable-impure-env
-  BIN_PATH = lib.makeBinPath [
-    # explicitly use nix, as e.g. lix does not have configurable-impure-env
-    pkgs.nix
-    # nixops error maybe due to our flake git hook: executing 'git': No such file or directory
-    pkgs.git
-  ];
 }

panel/nix/configuration.nix

@@ -178,10 +178,18 @@ in
       description = "${name} ASGI server";
       after = [ "network.target" ];
       wantedBy = [ "multi-user.target" ];
-      path = [
-        python-environment
-        manage-service
-      ];
+      path =
+        [
+          python-environment
+          manage-service
+        ]
+        ++ (
+          with pkgs;
+          lib.makeBinPath [
+            nix
+            git
+          ]
+        );
       preStart = ''
         # Auto-migrate on first run or if the package has changed
         versionFile="/var/lib/${name}/package-version"

panel/src/panel/settings.py

@@ -240,8 +240,6 @@ if user_settings_file is not None:
 #     The correct thing to do here would be using a helper function such as with `get_secret()` that will catch the exception and explain what's wrong and where to put the right values.
 #     Replacing the `USER_SETTINGS_FILE` mechanism following the comment there would probably be a good thing.
 
-# PATH to expose to launch button
-bin_path=env['BIN_PATH']
 # path of the root flake to trigger nixops from, see #94.
 # to deploy this should be specified, for dev just use a relative path.
 repo_dir = env["REPO_DIR"]

panel/src/panel/views.py

@@ -89,7 +89,7 @@ class DeploymentStatus(ConfigurationForm):
 
     def deployment(self, config: BaseModel):
         env = {
-            "PATH": settings.bin_path,
+            "PATH": os.environ.get("PATH"),
             # pass in form info to our deployment
             "DEPLOYMENT": config.json()
         }