Wave 7: four functions strict exact (hud_unit, flags, path, motion_sensor)

- _hud_render_unit_interface (3,504 B): January's local-player re-read for
  the HUD state, flag-macro draw flags, advancing shield color pointer,
  named auxiliary panel, direct flash-time indexing (park reopen)
- _flag_render_proper: loop counters reset in the for-initializers
- _path_state_begin: single exit, distance_squared3d + square_root, a
  destination pointer shared by the helper and the error text (park reopen)
- _blip_begin: January's caller pushes a zero second argument the callee
  never reads; the parameter is added with a provisional name and comment
  (park reopen). The caller park _render_motion_sensor is re-measured
  (non-exact before and after).

Rejected: _render_debug_trigger_volumes (duplicated arm stores), leaf_map
rows (owner-declined P7 projection_from_vector3d body),
_closest_point_to_attractor (point_from_line3d COMDAT).
Stable diff vs 9062b1e96: 0 regressions; parks 230 -> 226.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

source/objects/widgets/flags.c

@@ -714,7 +714,7 @@ void flag_render_proper(
 		struct flag_vertex_datum *corner10;
 		struct flag_vertex_datum *corner01;
 		struct flag_vertex_datum *corner11;
-		short vertex_index = 0;
+		short vertex_index;
 		short i;
 		short x;
 		short y;
@@ -726,7 +726,7 @@ void flag_render_proper(
 		one_over_height = 1.0f / (definition->height - 1);
 		csmemset(&vertex, 0, sizeof(vertex));
 
-		for (x = 0; x < definition->width; x++)
+		for (x = 0, vertex_index = 0; x < definition->width; x++)
 		{
 			for (y = 0; y < definition->height; y++, vertex_index++)
 			{
@@ -757,8 +757,7 @@ void flag_render_proper(
 			}
 		}
 
-		i = 0;
-		for (x = 0; x < definition->width - 1; x++)
+		for (x = 0, i = 0; x < definition->width - 1; x++)
 		{
 			for (y = 0; y < definition->height - 1; y++)
 			{