ResolveAgent aliased the default config's Temperature and MaxTokens
pointers into every agent that left them unset, so all resolved
agents shared one backing value. A mutation through any of those
pointers would corrupt the default and every other agent. It also
dereferenced the default unconditionally even though it can be nil.
Allocate a fresh pointer holding a copy of the default value, and
guard against a nil default so each resolved agent owns independent
state.
Signed-off-by: Émile Ré <emile@probo.com>
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