reject trailing characters in DecimalLocaleConverter.parse

[rootvector2]

DecimalLocaleConverter.parse calls DecimalFormat.parse(String), which stops at the first character it cannot read and silently drops the rest, so a locale numeric conversion of 123abc returns 123 and 42 OR 1=1 returns 42. Every numeric locale converter (Byte/Short/Integer/Long/Float/Double/BigDecimal/BigInteger) routes through this one method, while the sibling DateLocaleConverter and the non-locale NumberConverter already reject leftover input with a ParsePosition check. Found by comparing the locale number parsers against DateLocaleConverter; switched to that same check so the whole string must be consumed.

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