gh-106752: Move zipfile._path into its own package (#106753)

* gh-106752: Move zipfile._path into its own package so it may have supplementary behavior.

* Add blurb

Lib/test/test_zipfile/_path/test_complexity.py

@@ -0,0 +1,24 @@
+import unittest
+import string
+import zipfile
+
+from ._functools import compose
+from ._itertools import consume
+
+from ._support import import_or_skip
+
+
+big_o = import_or_skip('big_o')
+
+
+class TestComplexity(unittest.TestCase):
+    def test_implied_dirs_performance(self):
+        best, others = big_o.big_o(
+            compose(consume, zipfile.CompleteDirs._implied_dirs),
+            lambda size: [
+                '/'.join(string.ascii_lowercase + str(n)) for n in range(size)
+            ],
+            max_n=1000,
+            min_n=1,
+        )
+        assert best <= big_o.complexities.Linear