Adds a basic script for generating API docs from the mediapipe Python package

This is pretty bare-bones for now, but I need something to start wiring up the rest of the automation. Plus this should be easy enough for anyone to riff on once it's in place.

I couldn't find a great location within the existing directory structure for this, so LMK if it should be re-homed.

PiperOrigin-RevId: 484426543

docs/BUILD

@@ -0,0 +1,14 @@
+# Placeholder for internal Python strict binary compatibility macro.
+
+py_binary(
+    name = "build_py_api_docs",
+    srcs = ["build_py_api_docs.py"],
+    deps = [
+        "//mediapipe",
+        "//third_party/py/absl:app",
+        "//third_party/py/absl/flags",
+        "//third_party/py/tensorflow_docs",
+        "//third_party/py/tensorflow_docs/api_generator:generate_lib",
+        "//third_party/py/tensorflow_docs/api_generator:public_api",
+    ],
+)