fix(navigation): handle removed step in FlowHost proceed() (#798)

* refactor(ui): extract CircularIconButton and clean up TitleBar

Extract the private CircularIconButton from AppBarDefaults into a shared
top-level component with a (Dp) -> Unit content lambda. Update all call
sites in TitleBar to use the new size parameter, migrate material2 to
material3 imports in SearchInput, and adjust padding in
RegionSelectionModalContent after SearchInput lost its built-in
horizontal padding.

Signed-off-by: Brandon McAnsh <git@bmcreations.dev>

* fix(navigation): handle removed step in FlowHost proceed()

When the current step is removed from the steps list (e.g. a gate whose
condition is now met), proceed() now navigates to the first remaining
step instead of doing nothing.

Signed-off-by: Brandon McAnsh <git@bmcreations.dev>

---------

Signed-off-by: Brandon McAnsh <git@bmcreations.dev>

Author: bmc08gt

ui/navigation/src/main/kotlin/com/getcode/navigation/flow/FlowHost.kt

@@ -384,6 +384,10 @@ private class InnerFlowNavigator<S : FlowStep, R : Parcelable>(
         val nextIndex = anchorIndex + 1
         if (anchorIndex >= 0 && nextIndex <= currentSteps.lastIndex) {
             navigateTo(currentSteps[nextIndex])
+        } else if (anchorIndex < 0 && currentSteps.isNotEmpty()) {
+            // Current step was removed from the steps list (e.g. a gate whose condition
+            // is now met). Navigate to the first remaining step.
+            navigateTo(currentSteps.first(), popCurrent = true)
         } else {
             val result = completedResult()
             if (result != null) exitWithResult(result)