feat: accept days and weeks in --since and --until

tea issue list --since 7d was rejected; only h, m and s durations worked.
Time bounds such as --since, --until and --before now also take whole
days and weeks: 7d, 2w.

Signed-off-by: bircni <bircni@icloud.com>

internal/app/args.go

@@ -113,7 +113,7 @@ func (f positiveInt) Set(raw string) error {
 }
 
 func parseRunTime(value string, now time.Time) (*time.Time, error) {
-	if duration, err := time.ParseDuration(value); err == nil {
+	if duration, err := durationAgo(value); err == nil {
 		if duration < 0 {
 			return nil, errors.New("relative duration cannot be negative")
 		}
@@ -128,6 +128,20 @@ func parseRunTime(value string, now time.Time) (*time.Time, error) {
 	return nil, errors.New("use a date, RFC3339 timestamp, or duration such as 24h")
 }
 
+// durationAgo parses a duration like time.ParseDuration, and also whole days and weeks: 7d, 2w.
+func durationAgo(value string) (time.Duration, error) {
+	for unit, size := range map[string]time.Duration{"d": 24 * time.Hour, "w": 7 * 24 * time.Hour} {
+		if count, ok := strings.CutSuffix(value, unit); ok {
+			n, err := strconv.Atoi(count)
+			if err != nil {
+				return 0, err
+			}
+			return time.Duration(n) * size, nil
+		}
+	}
+	return time.ParseDuration(value)
+}
+
 // timeRange is a pair of lower and upper time bound flags.
 type timeRange struct {
 	flags  *pflag.FlagSet