Remove integration tests in config_extended_test.go that duplicate
unit tests in config_test.go for findLocalCheatpath. Remove redundant
fuzz functions (FuzzFindLocalCheatpathNearestWins, FuzzTagsStress),
a duplicate parse test (TestParseInvalidYAML), and a permanently-skipped
interactive test (TestPromptIntegration).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>