Initial conditions should have instructions & be selectable for all variables

Problem

The documentation does not make it clear how to set initial conditions. This is especially unclear for internal state variables such as the Windkessel pressure in an RCR bc or the chamber state variables.

Solution

The documentation should show examples of setting initial conditions for state variables.

Additional context

It is possible that some of these variables are initialized in some hard coded manner, to zero, estimated steady state only, etc. If this is the case, then code to set initial values for all possible variables should be added.

Code of Conduct

• I agree to follow this project's Code of Conduct and Contributing Guidelines

No files or tests are named. Start by locating the documentation and initialization handling for RCR Windkessel pressure and chamber state variables; determine which variables are already initialized and how. Done means the documentation includes examples for state-variable initial conditions and any unsupported or hard-coded cases are explicitly resolved or documented.