Simplify maneuver texture selection with direct array indexing

docs/planning/rendering-cleanup-plan.md

@@ -50,7 +50,7 @@ Remove all spacecraft texture-related code:
 - Update docs/technical_reference.md line 531 (references to render_body)
 - **PAUSE** for user review
 
-### Step 5: Simplify Maneuver Texture Selection
+### Step 5: Simplify Maneuver Texture Selection [COMPLETED]
 - Replace switch statement (renderer.cpp:426-449) with direct array indexing
 - Since BurnDirection enum values are sequential (0-5), use `maneuver->direction` directly as texture_index
 - Handle BURN_CUSTOM case separately if needed

src/renderer.cpp

@@ -348,30 +348,7 @@ void render_maneuver_marker_screen_space(Spacecraft* craft, Maneuver* maneuver,
     if (screen_size < 20.0f) screen_size = 20.0f;
     if (screen_size > 60.0f) screen_size = 60.0f;
 
-    int texture_index;
-    switch (maneuver->direction) {
-        case BURN_PROGRADE:
-            texture_index = 0;
-            break;
-        case BURN_RETROGRADE:
-            texture_index = 1;
-            break;
-        case BURN_NORMAL:
-            texture_index = 2;
-            break;
-        case BURN_ANTINORMAL:
-            texture_index = 3;
-            break;
-        case BURN_RADIAL_IN:
-            texture_index = 4;
-            break;
-        case BURN_RADIAL_OUT:
-            texture_index = 5;
-            break;
-        default:
-            texture_index = 0;
-            break;
-    }
+    int texture_index = (maneuver->direction == BURN_CUSTOM) ? 0 : maneuver->direction;
 
     Rectangle source = {0, 0, 32, 32};
     Rectangle dest = {