Hello, I would like to know if caravel chip has build-in current source for analog application (stable with temperature or VDD variation) ?

Not in the existing caravel chip, but I have a current bias generator design here: https://github.com/RTimothyEdwards/sky130_ef_ip__biasgen. It is not temperature-stable by itself, but it can be made temperature-stable with a bandgap or voltage reference such as this one: https://github.com/efabless/sky130_ak_ip__cmos_vref. The bias generator is silicon proven; the voltage reference is in manufacture and has not been tested in silicon yet.