[common] Range-check the digit guard in DateTimeUtils

[LuciferYang]

Purpose

close #9648

DateTimeUtils.parseDate and parseTime return null for input they cannot parse, and they guard every Integer.parseInt with isInteger. That guard only checked the characters:

private static boolean isInteger(String s) {
    boolean isInt = s.length() > 0;
    for (int i = 0; i < s.length(); i++) {
        if (s.charAt(i) < '0' || s.charAt(i) > '9') {
            isInt = false;
            break;
        }
    }
    return isInt;
}

A component of eleven digits therefore passed it and Integer.parseInt threw NumberFormatException, escaping a method whose every other failure path returns null. parseDate("2147483648-01-01") and parseTime("2147483648:00:00") both do it.

The guard now also checks the range, which is enough because it sits in front of each of the eleven parseInt calls in those two methods. Nothing else changes: no signature, no local variable type, no arithmetic.

Callers see the difference as an exception type. Through the casts, NumberFormatException becomes the DateTimeException that BinaryStringUtils.toDate raises for any unparseable string, which is what a caller already gets for "99999-01-01" (rejected by isIllegalDate) or "not-a-date". The Hive PaimonTimeObjectInspector.convert passes the Integer through, so a TIME column holding such a value writes NULL rather than failing, matching what it already does for other invalid times.

Tests

DateTimeUtilsTest.testParseDateAndTimeOverflowReturnsNull covers a too-large year, month, day and hour, and the two boundary cases: 2147483648 is the smallest ten-digit value that does not fit an int, and 2147483647 does fit but is still not a valid year, so both have to come back null through different branches. Valid values are asserted alongside them.

Against the unfixed guard the test errors with NumberFormatException: For input string: "2147483648".

mvn -pl paimon-common -Dtest=DateTimeUtilsTest test on JDK 8: 12 tests, 0 failures. spotless:check and checkstyle:check on paimon-common are clean.