Added a parameter to allow severity-based formatting for
diagnostic messages. Defaults to 'info'.
This update enables better control over message presentation
(e.g., coloring) based on severity levels such as 'info', 'warn',
and 'error'.

Refs: nodejs#55922

Updated to process the parameter for events. Messages
are now formatted with colors based on the
(e.g., 'info', 'warn', 'error').
This change ensures diagnostic messages are visually distinct,
improving clarity and reducing debugging effort during test runs.

Refs: nodejs#55922

Enhanced  to include colors for the following
diagnostic levels:
 : blue - info
 : yellow - warn
 : red - error

Refs: nodejs#55922

Updated coverage threshold checks in to use the
parameter when calling. Errors now use the
'error' level for red-colored formatting.
This ensures coverage errors are highlighted effectively in the output.

Fixes: nodejs#55922

implemented requested change by removing debug
from reporterColorMap

Refs: nodejs#55964 (review)

updated the documentation for the 'test:diagnostic' event to
include the new level parameter. clarified its purpose, default
value, and possible severity levels ('info', 'warn',
'error').

Fixes: nodejs#55922

Add a test in  to verify that
the diagnostic error messages about unmet coverage thresholds
are displayed in red when using the spec reporter.

Fixes: nodejs#55922

Added eslint-disable comment to bypass no-control-regex.
This allows testing ANSI escape sequences for red color
in error messages without triggering lint errors.

Fixes: nodejs#55922

Updated the description of the  parameter to note
that color output is specific to the spec reporter. This
helps users understand its behavior and create custom
reporters with accurate expectations.

Fixes: nodejs#55922