perf test: Truncate printed test descriptions dynamically to avoid terminal wrapping

perf test: Truncate printed test descriptions dynamically to avoid terminal wrapping

When test descriptions are extremely long (e.g., the truncated perf.data
graceful handling test is 103 characters long), they wrap across terminal
boundaries.

Because the ANSI escape code to delete the line (PERF_COLOR_DELETE_LINE)
only clears a single terminal line, visual wrapping leaves orphan
wrapped lines on the screen, which results in the test description being
printed multiple times.

Resolve this by checking the terminal width (get_term_dimensions) and
dynamically truncating the printed test description to fit within the
available columns, leaving safety space for the prefix index and status
suffix.

Also, remove the width padding from the test suite headers which do not
display inline status messages. This prevents their trailing colons from
wrapping onto new lines on standard width terminals.

Finally, avoid GCC 16's -Wformat-truncation warnings by delegating the
description padding to pr_info's %-*s format specifier instead of padding
within a temporary buffer, and clamp the truncation limit to the temporary
buffer's size.

JUnit XML output and the failure summary report still print the full,
untruncated test descriptions.

Assisted-by: Gemini-CLI:Google Gemini 3.1 Pro
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>