feat: Safety Goals + Drive-Away-Assist + vollst. Traceability

Neue Layer:
- safety/sg/SG-001..005 als eigene Doorstop-Items (ASIL D/D/A/C/B)
- SYS-Reqs verlinken nach oben auf SG via frontmatter
- Kette ist jetzt: SG -> SYS -> SA, SWE -> SWA -> Code (@arch) + Test (@reqs)

Drive-Away-Assist im Safety Manager:
- SWE-011 (Anfahrabsicht erkennen) implementiert
- SWE-012 (Sicherheits-Check Tuer + Gurt) implementiert
- Neuer State SAFETY_DRIVE_AWAY + safety_mgr_release_requested()
- SafetyInputs erweitert um gas_pedal_percent, gear_in_drive,
  door_closed, seatbelt_fastened
- 5 neue Tests (DRIVE_AWAY armed/blocked/end-conditions)
- Test-Header @reqs erweitert auf SWE-007..012

traceability.py erweitert:
- SG als neuer Top-Level
- Code-Mapping-Check: @arch im Header von src/*.c muss SWA-id matchen
- Test-Mapping-Check: @reqs im Header der Tests muss alle SWE der
  zugehoerigen SWA abdecken
- HTML zeigt 7 Spalten: SG | SYS | SA | SWE | SWA | Code | Test
- 2 zusaetzliche Tabellen: Code->Arch und Test->Reqs

test_apply_controller.c:
- @reqs Header um SWE-005 ergaenzt (war funktional drin, nur Tag fehlte)

Counts:
- 55 doorstop-Items (war 50)
- 46 Unit-Tests (war 41)
- Traceability vollstaendig in beide Richtungen

tests/unit/test_safety_manager.c

@@ -2,7 +2,7 @@
  * @file test_safety_manager.c
  * @brief Unit-Tests fuer den Safety Manager (ASIL-D).
  *
- * @reqs SWE-007 SWE-008 SWE-009 SWE-010
+ * @reqs SWE-007 SWE-008 SWE-009 SWE-010 SWE-011 SWE-012
  * @arch SWA-001
  */
 #include "../unit_test_framework.h"
@@ -207,6 +207,90 @@ static void test_hillhold_armed_to_idle_if_grade_drops(void)
 
 /* ---- Mutually exclusive: nicht in beiden Modi gleichzeitig ---- */
 
+/* ---- Drive-Away-Assist (SWE-011 + SWE-012) ---- */
+
+static SafetyInputs make_applied_at_rest(void)
+{
+    SafetyInputs in = {0};
+    in.engine_running       = true;
+    in.brake_pedal_pressed  = false;
+    in.vehicle_speed_kmh    = 0.0f;
+    in.grade_percent        = 0.0f;
+    in.current_state        = EPB_STATE_APPLIED;
+    in.gas_pedal_percent    = 0.0f;
+    in.gear_in_drive        = false;
+    in.door_closed          = true;
+    in.seatbelt_fastened    = true;
+    return in;
+}
+
+static void test_drive_away_armed_on_intent(void)
+{
+    TEST_BEGIN("SWE-011 + SWE-012: Anfahrabsicht + Safety -> DRIVE_AWAY + Release-Request");
+    (void)safety_mgr_init();
+    SafetyInputs in = make_applied_at_rest();
+    in.gas_pedal_percent = 25.0f;
+    in.gear_in_drive     = true;
+    safety_mgr_step_50ms(&in);
+    ASSERT_EQ(safety_mgr_get_state(), SAFETY_DRIVE_AWAY);
+    ASSERT_TRUE(safety_mgr_release_requested());
+    TEST_END();
+}
+
+static void test_drive_away_blocked_without_safety(void)
+{
+    TEST_BEGIN("SWE-012: Tuer offen blockiert Drive-Away");
+    (void)safety_mgr_init();
+    SafetyInputs in = make_applied_at_rest();
+    in.gas_pedal_percent = 25.0f;
+    in.gear_in_drive     = true;
+    in.door_closed       = false;  /* Tuer offen */
+    safety_mgr_step_50ms(&in);
+    ASSERT_EQ(safety_mgr_get_state(), SAFETY_IDLE);
+    ASSERT_TRUE(!safety_mgr_release_requested());
+    TEST_END();
+}
+
+static void test_drive_away_blocked_without_seatbelt(void)
+{
+    TEST_BEGIN("SWE-012: Gurt nicht angelegt blockiert Drive-Away");
+    (void)safety_mgr_init();
+    SafetyInputs in = make_applied_at_rest();
+    in.gas_pedal_percent = 25.0f;
+    in.gear_in_drive     = true;
+    in.seatbelt_fastened = false;
+    safety_mgr_step_50ms(&in);
+    ASSERT_EQ(safety_mgr_get_state(), SAFETY_IDLE);
+    TEST_END();
+}
+
+static void test_drive_away_blocked_below_gas_threshold(void)
+{
+    TEST_BEGIN("SWE-011: Gas < 10% loest kein Drive-Away aus");
+    (void)safety_mgr_init();
+    SafetyInputs in = make_applied_at_rest();
+    in.gas_pedal_percent = 5.0f;
+    in.gear_in_drive     = true;
+    safety_mgr_step_50ms(&in);
+    ASSERT_EQ(safety_mgr_get_state(), SAFETY_IDLE);
+    TEST_END();
+}
+
+static void test_drive_away_ends_when_released(void)
+{
+    TEST_BEGIN("DRIVE_AWAY -> IDLE wenn Apply Controller geloest hat");
+    (void)safety_mgr_init();
+    SafetyInputs in = make_applied_at_rest();
+    in.gas_pedal_percent = 25.0f;
+    in.gear_in_drive     = true;
+    safety_mgr_step_50ms(&in);  /* -> DRIVE_AWAY */
+    in.current_state = EPB_STATE_RELEASED;
+    safety_mgr_step_50ms(&in);
+    ASSERT_EQ(safety_mgr_get_state(), SAFETY_IDLE);
+    ASSERT_TRUE(!safety_mgr_release_requested());
+    TEST_END();
+}
+
 static void test_already_applied_does_not_arm_auto_apply(void)
 {
     TEST_BEGIN("Bereits Applied: kein Auto-Apply Arming");
@@ -235,6 +319,11 @@ int main(void)
     test_hillhold_active_on_brake_release();
     test_hillhold_active_ends_on_vehicle_rolling();
     test_hillhold_armed_to_idle_if_grade_drops();
+    test_drive_away_armed_on_intent();
+    test_drive_away_blocked_without_safety();
+    test_drive_away_blocked_without_seatbelt();
+    test_drive_away_blocked_below_gas_threshold();
+    test_drive_away_ends_when_released();
     test_already_applied_does_not_arm_auto_apply();
     TEST_SUMMARY();
 }