When all typed catch blocks failed to match a thrown exception's type,
handle_exception() would silently discard the exception and return a
default-constructed Boxed_Value instead of propagating it. This meant
code like `try { throw(42) } catch(string e) { }` would swallow the
int exception rather than letting it propagate to an outer handler.
The fix adds an explicit re-throw when no catch block matches, and
restructures eval_internal() with a nested try/catch to ensure the
finally block still executes before the unhandled exception propagates.
Co-authored-by: leftibot <leftibot@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>