share one loadTestConfig() helper across the tests

19 test translation units each defined an identical local loadConfig().
They now include src/test/TestConfig.h, which lives off the lib/ui/app
include path like SimulationTestAccess.h.

Co-Authored-By: Claude <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GH8ZMRY3vhxxXcaUxBqxkk

src/test/DeterminismTest.cpp

@@ -11,14 +11,10 @@
 #include "SimulationTestAccess.h"
 #include "StateChecksum.h"
 #include "Tick.h"
+#include "TestConfig.h"
 
 namespace
 {
-GameConfig loadConfig()
-{
-    return ConfigLoader::loadFromDirectory(CONFIG_DIR);
-}
-
 constexpr int kScriptTicks = 2000;
 
 // Runs a fixed scripted session and returns the full-state checksum after every
@@ -26,7 +22,7 @@ constexpr int kScriptTicks = 2000;
 // otherwise lets waves/combat run so the RNG stream and ECS state are exercised.
 std::vector<std::uint64_t> runScriptedSession(unsigned int seed)
 {
-    Simulation sim(loadConfig(), seed);
+    Simulation sim(loadTestConfig(), seed);
 
     // Tick 0: a miner feeding a short belt line on the asteroid.
     SimulationTestAccess::place(sim, BuildingType::Miner, QPoint(-3, 0), Rotation::East);
@@ -121,8 +117,8 @@ TEST_CASE("fingerprintRng: equal states match, advanced states differ", "[determ
 
 TEST_CASE("Simulation::rngFingerprint is stable for equal seeds", "[determinism]")
 {
-    const Simulation a(loadConfig(), 777);
-    const Simulation b(loadConfig(), 777);
+    const Simulation a(loadTestConfig(), 777);
+    const Simulation b(loadTestConfig(), 777);
 
     REQUIRE(a.getRngFingerprint() == b.getRngFingerprint());
 }