Render a human-readable, ANSI-free diff between a baseline template and the
current synthesized template (read from disk). Used to enrich baseline-drift
failure messages so the actual changed resources/properties are visible in CI
logs (the toolkit's own diff dump is suppressed via logLevel 'error').
Returns an indented diff block, or '' if it can't be produced.
Render a human-readable, ANSI-free diff between a baseline template and the current synthesized template (read from disk). Used to enrich baseline-drift failure messages so the actual changed resources/properties are visible in CI logs (the toolkit's own diff dump is suppressed via logLevel 'error'). Returns an indented diff block, or '' if it can't be produced.