Text can be added in parts due to the presence
of the <tspan> tag. This requires that each
subsequent piece of text is appended rather than
overwriting the previous one.
The string passed to the svg parser is not guaranteed to always be a valid string.
Certain strings may have numbers that cannot be converted.
Therefore, make sure to check whether the converted value is in the appropriate range before returning.
related issue: https://github.com/thorvg/thorvg/issues/2078#issuecomment-2037495121
