Fix documentation warnings generated by JavaDoc (NFC) (#3428)

Some C++ Doxygen comments were updated to reflect any wording changes.

See `rg "(@return|@param \w+) TODO" | less` for list of incomplete docs.

wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/PIDBase.java

@@ -307,6 +307,8 @@ public class PIDBase implements PIDInterface, PIDOutput, Sendable, AutoCloseable
    * setpoint for the output. If a position PID controller is being used, the F term should be set
    * to 1 over the maximum speed for the output measured in setpoint units per this controller's
    * update period (see the default period in this class's constructor).
+   *
+   * @return The feedforward value.
    */
   protected double calculateFeedForward() {
     if (m_pidInput.getPIDSourceType().equals(PIDSourceType.kRate)) {