Add dotenv generator

usage as such `-g dotenv`
Should also be abble to make the PyCharmRunEnv generators absolete, but untested.

PyCharm allows for setting a `.env` file for a script such as `cura_app.py`

Contributes to NP-822

extensions/generators/dotenv.py

@@ -0,0 +1,22 @@
+import os
+from conan.tools.env import VirtualRunEnv
+from conan.tools.files import copy, save, load
+
+class dotenv:
+
+    def __init__(self, conanfile):
+        self._conanfile = conanfile
+
+    def generate(self):
+        run_env = VirtualRunEnv(self._conanfile)
+        env = run_env.environment()
+        env_vars = env.vars(self._conanfile, scope="run")
+        output_file = ".env"
+        self._conanfile.output.info(f"Generating '{output_file}' with run environment variables...")
+
+        content = ""
+        for key, value in env_vars.items():
+            content += f"{key}={value}\n"
+        self._conanfile.output.info(f"'{output_file}' generated successfully.")
+        save(self._conanfile, output_file, content)
+        self._conanfile.output.info(f"Saved '{output_file}' to the current directory.")