feat: restructure renamer package and implement media extraction features

- Updated `pyproject.toml` to reflect new package structure.
- Created `renamer/__init__.py` to initialize the package.
- Implemented `RenamerApp` in `renamer/app.py` for the main application interface.
- Added constants for video extensions in `renamer/constants.py`.
- Developed `MediaExtractor` class in `renamer/extractor.py` for extracting metadata from media files.
- Created various extractor classes in `renamer/extractors/` for handling filename, metadata, and media info extraction.
- Added formatting classes in `renamer/formatters/` for displaying media information and proposed filenames.
- Implemented utility functions in `renamer/utils.py` for detecting file types and extracting media track information.
- Introduced `OpenScreen` in `renamer/screens.py` for user input of directory paths.
- Enhanced error handling and user feedback throughout the application.

renamer/screens.py

@@ -0,0 +1,30 @@
+from textual.screen import Screen
+from textual.widgets import Input, Button
+from pathlib import Path
+
+
+class OpenScreen(Screen):
+    def compose(self):
+        yield Input(placeholder="Enter directory path", value=".", id="dir_input")
+        yield Button("OK", id="ok")
+
+    def on_button_pressed(self, event):
+        if event.button.id == "ok":
+            self.submit_path()
+
+    def on_input_submitted(self, event):
+        self.submit_path()
+
+    def submit_path(self):
+        path_str = self.query_one("#dir_input", Input).value
+        path = Path(path_str)
+        if not path.exists():
+            # Show error
+            self.query_one("#dir_input", Input).value = f"Path does not exist: {path_str}"
+            return
+        if not path.is_dir():
+            self.query_one("#dir_input", Input).value = f"Not a directory: {path_str}"
+            return
+        self.app.scan_dir = path
+        self.app.scan_files()
+        self.app.pop_screen()