Honour enable_camera and skip camera profiles when no real camera is used

config/config.example.ini

@@ -217,6 +217,8 @@ output_dir =
 ; Enable/disable subsystems and select mock (simulated) implementations.
 ; CLI flags (e.g. --no-mqtt, --mock-camera, --mock-serial) override these.
 enable_mqtt = true
+; false: open no camera at all - a mock source stands in, no Vimba X needed and
+; no profile XMLs required. For bringing a tower up one subsystem at a time.
 enable_camera = true
 enable_serial = true
 enable_imu = false

src/core/Application.cpp

@@ -340,12 +340,33 @@ struct Application::Impl {
                                                 std::chrono::milliseconds(cfg.env.period_ms));
     }
 
-    std::unique_ptr<ICameraSource> makeCamera() {
-        bool mock = opts.mock_camera.value_or(cfg.features.mock_camera);
+    // Does this run drive a real camera? Asked in two places - makeCamera() and
+    // the startup sequence, which must agree: profiles are meaningful only to
+    // VimbaCameraSource, so loading them for a mock run demands settings XMLs
+    // that a tower being brought up one subsystem at a time does not have yet.
+    //
+    // enable_camera substitutes the mock source rather than leaving `camera`
+    // null, because the capture path dereferences it in a dozen places. The
+    // result is a run with no camera hardware and no Vimba dependency, which is
+    // what the flag is for; it is not a silent no-op, and says so at startup.
+    bool realCameraWanted() const {
 #if !FGC_WITH_VIMBA
-        if (!mock) {
+        return false;
+#else
+        if (!cfg.features.enable_camera) return false;
+        return !opts.mock_camera.value_or(cfg.features.mock_camera);
+#endif
+    }
+
+    std::unique_ptr<ICameraSource> makeCamera() {
+        bool mock = !realCameraWanted();
+        if (mock && !cfg.features.enable_camera) {
+            LOG_WARN << "camera disabled ([Features] enable_camera = false); using a mock source "
+                        "- no images come from hardware in this run";
+        }
+#if !FGC_WITH_VIMBA
+        if (!opts.mock_camera.value_or(cfg.features.mock_camera) && cfg.features.enable_camera) {
             LOG_WARN << "Camera requested but binary built without Vimba X; using mock camera";
-            mock = true;
         }
 #endif
         const auto active = cfg.camera.active();
@@ -1990,7 +2011,15 @@ struct Application::Impl {
         if (Logger::categories())
             LOG_INFO << "wire trace enabled: " << traceNames(Logger::categories());
 
-        loadProfiles();  // before makeCamera(): the profile is applied at start()
+        // Before makeCamera(): the profile is applied at start(). Skipped entirely
+        // for a mock or disabled camera - a settings XML configures a physical
+        // sensor and nothing else, so requiring one would block bringing a tower
+        // up in phases (docs/tower-installation.md section 10).
+        if (realCameraWanted()) {
+            loadProfiles();
+        } else {
+            LOG_INFO << "camera profiles not loaded: no real camera in this run";
+        }
 
         channel = makeChannel();
         motor   = makeMotor();