add proper Python packaging with pyproject.toml

Add build-system section, move dev deps to optional, add MANIFEST.in
for C++/Cython source distribution, and export BASEDIR/INCLUDE_PATH
from __init__.py for consumers.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

MANIFEST.in

@@ -0,0 +1 @@
+recursive-include msgq *.h *.cc *.pyx *.pxd

msgq/__init__.py

@@ -1,4 +1,8 @@
-# must be built with scons
+import os
+
+BASEDIR = os.path.dirname(os.path.abspath(__file__))
+INCLUDE_PATH = os.path.abspath(os.path.join(BASEDIR, "../"))
+
 from msgq.ipc_pyx import Context, Poller, SubSocket, PubSocket, SocketEventHandle, toggle_fake_events, \
                                 set_fake_prefix, get_fake_prefix, delete_fake_prefix, wait_for_one_event
 from msgq.ipc_pyx import MultiplePublishersError, IpcError

pyproject.toml

@@ -1,33 +1,34 @@
 [project]
 name = "msgq"
-version = "0.0.1"
-description = "Code powering the comma.ai panda"
-readme = "README.md"
+version = "0.1.0"
+description = "Lock-free IPC message queue and VisionIPC"
 requires-python = ">=3.11,<3.13"
 license = {text = "MIT"}
 authors = [{name = "comma.ai"}]
-classifiers = [
-  "Natural Language :: English",
-  "Programming Language :: Python :: 3",
-  "Topic :: System :: Hardware",
-]
 dependencies = [
-  "setuptools",  # for distutils
-  "Cython",
-  "scons",
-  "ruff",
-  "parameterized",
-  "coverage",
   "numpy",
-  "pytest",
-  "pytest-retry",
-  "cppcheck",
-  "cpplint",
-  "codespell",
-  "ty",
-  "lefthook",
 ]
 
+[project.optional-dependencies]
+dev = [
+  "setuptools", "Cython", "scons", "ruff",
+  "parameterized", "coverage", "numpy",
+  "pytest", "pytest-retry",
+  "cppcheck", "cpplint", "codespell", "ty", "lefthook",
+]
+
+[build-system]
+requires = ["setuptools"]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools]
+include-package-data = true
+
+[tool.setuptools.package-data]
+"msgq" = ["*.h", "*.cc", "*.pyx", "*.pxd"]
+"msgq.visionipc" = ["*.h", "*.cc", "*.pyx", "*.pxd"]
+"msgq.logger" = ["*.h"]
+
 # https://beta.ruff.rs/docs/configuration/#using-pyprojecttoml
 [tool.ruff]
 lint.select = ["E", "F", "W", "PIE", "C4", "ISC", "RUF100", "A"]