broker: initialize drops the dataset's bearer tokens and everything they protected

Initialize is the fresh start between users. It already cleared the
images, plots, scan result and live rugnux status; it now also drops the
tokens, resets the dataset settings (name, file prefix, unit cell, ...)
to their defaults and forgets the last collection followed through
/live/events, so after it nothing of the previous dataset is readable,
with or without its token - the broker is as open and as empty as a
freshly started one.

The auth test checks that after /initialize the data-collection
statistics and the /statistics aggregate are open and no longer carry
the previous dataset's name. SECURITY.md also lists /rugnux/status
among the protected endpoints.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PXc1zD1yxHqaR1DGdCTHL4

tests/BrokerHttpAuthTest.cpp

@@ -110,6 +110,20 @@ TEST_CASE("JFJochBrokerHttp_BearerTokens", "[broker]") {
         REQUIRE(client.Get("/live/events", good)->status == 409);
     }
 
+    SECTION("initialize drops the tokens and everything they protected") {
+        REQUIRE(client.Post("/initialize")->status == 200);
+        for (int i = 0; i < 120 && nlohmann::json::parse(client.Get("/status")->body).at("state") != "Idle"; i++)
+            std::this_thread::sleep_for(std::chrono::milliseconds(500));
+        auto res = client.Get("/statistics/data_collection");
+        REQUIRE(res->status == 200);
+        REQUIRE(res->body.find("protected_run") == std::string::npos);
+        auto stats = client.Get("/statistics");
+        REQUIRE(stats->status == 200);
+        REQUIRE(stats->body.find("protected_run") == std::string::npos);
+        REQUIRE(client.Get("/rugnux/status")->status == 200);
+        REQUIRE(client.Get("/result/scan")->status != 401);
+    }
+
     SECTION("the control plane and the broker status stay open") {
         REQUIRE(client.Get("/status")->status == 200);
         REQUIRE(client.Get("/image_buffer/status")->status == 200);
@@ -122,11 +136,11 @@ TEST_CASE("JFJochBrokerHttp_BearerTokens", "[broker]") {
         nlohmann::json body = {{"beam_x_pxl", 1000}, {"beam_y_pxl", 1000},
                                {"detector_distance_mm", 100}, {"incident_energy_keV", 12.4}};
         REQUIRE(client.Post("/start", body.dump(), "application/json")->status == 500);
-        REQUIRE(client.Post("/initialize")->status == 200);
         REQUIRE(client.Get("/statistics/data_collection")->status == 401);
         REQUIRE(client.Get("/statistics/data_collection", good)->status == 200);
 
-        // The next start without tokens lifts the protection.
+        // Back from Inactive; the next start without tokens leaves the dataset open.
+        REQUIRE(client.Post("/initialize")->status == 200);
         start(nlohmann::json::object());
         REQUIRE(client.Get("/statistics/data_collection")->status == 200);
         REQUIRE(client.Get("/statistics/data_collection", wrong)->status == 200);