tweak(batch): up restrictive max batch tool from `10` to `25` - add tool execution stagger (50ms) so it looks cooler

[spoons-and-mirrors]

What does this PR do?

This PR ups the max tool number batch can accept from 10 to 25 (I had originally set 10 thinking it was fine, but I now realise that it was somewhat arbitrary and doesn't necessarily plays well with models such as GPT 5.x

This PR also staggers the tool calling by 50ms, which gives a much better visual experience of the batch tool (UX win for a maximum of 1sec additional latency on the whole batch execution)

I initially had hopes it would fix the random tool duplication that happens when using batch, but this one is still out there...

How did you verify your code works?

Used it, works as expected.