Welcome to the community Nafula sounds like a really exciting project, especially the Sheng/code-switching handling.
I can help point you in the right direction on the credits issue. The trial ceiling you've hit is an account-level limit that resets or unlocks when you move to a paid plan it's not something that can be extended on the trial tier itself.
For Developer Grants or sponsored credits, Anthropic does have programs for builders working on impactful projects have you already applied through their official credits request form, or are you looking for a workaround in the meantime?