|  | Add 106 unit tests with full coverage for move-buffer-and-file (51 tests)
  and rename-buffer-and-file (55 tests). Refactor both functions using
  interactive/non-interactive split pattern for simpler testing and reusability.
  Changes:
  - Split cj/move-buffer-and-file and cj/rename-buffer-and-file into internal
    implementations (cj/--*) and interactive wrappers
  - Add ok-if-exists parameter with user confirmation to prevent data loss
  - Fix bugs: return values, path expansion, string-match arg order, regex
  - Add test utilities for proper buffer cleanup and isolation
  - Document interactive/non-interactive pattern in quality-engineer.org
  - Document error message testing guidelines in quality-engineer.org
  All 106 tests passing. |