Re-license @ag-ui/mastra

[justinedelson]

Given that Mastra has been switched to the Apache license (see e.g. mastra-ai/mastra#5765), would it make sense to switch @ag-ui/mastra from Elastic to Apache as well?

[NathanTarbert]

Hey @justinedelson, thanks for flagging this.

Yes, I will submit a PR for this.

[NathanTarbert]

#225

[justinedelson]

Thanks @NathanTarbert

[NathanTarbert]

@justinedelson, merged!