0.1 update, make the stop container code more robust and fix some bugs, update the about screen for version 0.1

tests/test_stop_waiter.cpp

@@ -0,0 +1,33 @@
+#include "stop_waiter.hpp"
+
+#include <cassert>
+#include <chrono>
+#include <iostream>
+
+int main() {
+    int calls = 0;
+    const auto stopped = waitForStopped([&] {
+        return ++calls < 3 ? StopProbe::Running : StopProbe::Stopped;
+    },
+                                        std::chrono::milliseconds(100),
+                                        std::chrono::milliseconds(1));
+    assert(stopped == StopProbe::Stopped);
+
+    const auto timed_out = waitForStopped([] { return StopProbe::Unknown; },
+                                          std::chrono::milliseconds(5),
+                                          std::chrono::milliseconds(1));
+    assert(timed_out == StopProbe::Unknown);
+    int transient_calls = 0;
+    const auto transient = waitForStopped([&] {
+        ++transient_calls;
+        if (transient_calls < 3) return StopProbe::Unknown;
+        return StopProbe::Stopped;
+    }, std::chrono::milliseconds(100), std::chrono::milliseconds(1));
+    assert(transient == StopProbe::Stopped);
+    // A failed refresh must not be interpreted as a stopped state.
+    const auto preserved = waitForStopped([] { return StopProbe::Unknown; },
+                                          std::chrono::milliseconds(3),
+                                          std::chrono::milliseconds(1));
+    assert(preserved == StopProbe::Unknown);
+    std::cout << "Stop waiter tests passed\n";
+}