feat: Support day unit with edgex-dto-duration validation tag

[lindseysimple]

Resolves #1013. Support day unit in edgex-dto-duration validation tag.

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Testing Instructions

New Dependency Instructions (If applicable)

[judehung]

The time.ParseDuration is capable of summing up repeated time units inside the duration string. For example, time.ParseDuration("1h30m10m1h") will return a duration 2h40m0s. To be consistent with such behavior, the implementation of parseDurationWithDay should be capable of doing same thing to sum up repeated d time unit. Below is a revised version of parseDurationWithDay to achieve this:

func parseDurationWithDay(durationStr string) (bool, time.Duration) {
	var totalDuration time.Duration

	// Regex to find all day fragments like "2.2d", "1.5d", etc.
	re := regexp.MustCompile(`([\d.]+)d`)
	matches := re.FindAllStringSubmatch(durationStr, -1)

	// Sum up all matched day durations
	for _, match := range matches {
		if len(match) != 2 {
			continue
		}
		dayVal, err := strconv.ParseFloat(match[1], 64)
		if err != nil {
			return false, 0
		}
		totalDuration += time.Duration(dayVal * float64(24*time.Hour))
	}

	// Remove all day fragments from the original string to get the rest
	durationStr = re.ReplaceAllString(durationStr, "")
	durationStr = strings.TrimSpace(durationStr)

	// Parse the remaining standard duration if any (e.g., "5h30m")
	if durationStr != "" {
		remainingDuration, err := time.ParseDuration(durationStr)
		if err != nil {
			return false, totalDuration
		}
		totalDuration += remainingDuration
	}

	return true, totalDuration
}

We should also unit tests to cover such edge case, e.g. 2.2d1.1d20m3h1h10m is parsed to 83h42m0s.

[lindseysimple]

Thanks for pointing out the repeated day units case which I didn't think of.
Modified and unit test added.

[judehung]

LGTM