Fix lint and mypy errors

- Remove whitespace from blank lines in docstrings (ruff W293)
- Use !r format specifier for bytes in f-string (mypy str-bytes-safe)

git/diff.py

@@ -116,7 +116,7 @@ def decode_path(path: bytes, has_ab_prefix: bool = True) -> Optional[bytes]:
         # Support standard (a/b) and mnemonicPrefix (c/w/i/o/h) prefixes
         # See git-config diff.mnemonicPrefix documentation
         valid_prefixes = (b"a/", b"b/", b"c/", b"w/", b"i/", b"o/", b"h/")
-        assert any(path.startswith(p) for p in valid_prefixes), f"Unexpected path prefix: {path[:10]}"
+        assert any(path.startswith(p) for p in valid_prefixes), f"Unexpected path prefix: {path[:10]!r}"
         path = path[2:]
 
     return path

test/test_diff.py

@@ -283,14 +283,14 @@ def test_diff_unsafe_paths(self):
 
     def test_diff_mnemonic_prefix(self):
         """Test that diff parsing works with mnemonicPrefix enabled.
-        
+
         When diff.mnemonicPrefix=true is set in git config, git uses different
         prefixes for diff paths:
         - c/ for commit
-        - w/ for worktree  
+        - w/ for worktree
         - i/ for index
         - o/ for object
-        
+
         This addresses issue #2013 where the regex only matched [ab]/ prefixes.
         """
         # Create a diff with mnemonicPrefix-style c/ and w/ prefixes
@@ -305,7 +305,7 @@ def test_diff_mnemonic_prefix(self):
 """
         diff_proc = StringProcessAdapter(diff_mnemonic)
         diffs = Diff._index_from_patch_format(self.rorepo, diff_proc)
-        
+
         # Should parse successfully (previously would fail or return empty)
         self.assertEqual(len(diffs), 1)
         diff = diffs[0]