Add type stubs for mido MIDI library

- Created type stubs for various modules in the mido library including messages, midifiles, parser, ports, sockets, syx, tokenizer, and version.
- Implemented type hints for functions and classes to improve type checking and code clarity.
- Added support for MIDI over TCP/IP in sockets module.
- Included methods for reading and writing SYX files in syx module.
- Enhanced the parser functionality with a dedicated Parser class for MIDI byte streams.
- Established a structure for MIDI file handling with MidiFile and MidiTrack classes.

typings/mido/midifiles/__init__.pyi

@@ -0,0 +1,21 @@
+"""
+This type stub file was generated by pyright.
+"""
+
+from .meta import KeySignatureError, MetaMessage, UnknownMetaMessage
+from .midifiles import MidiFile
+from .tracks import MidiTrack, merge_tracks
+from .units import bpm2tempo, second2tick, tempo2bpm, tick2second
+
+__all__ = [
+    "KeySignatureError",
+    "MetaMessage",
+    "MidiFile",
+    "MidiTrack",
+    "UnknownMetaMessage",
+    "bpm2tempo",
+    "merge_tracks",
+    "second2tick",
+    "tempo2bpm",
+    "tick2second",
+]