gui: fix software panel flickering and adjust column layout

The software list panel suffered from noticeable flickering when
scrolling due to unnecessary redraws:

- The cycle button (Libraries/Devices/Resources) was redrawn on every
  scroll operation even though its label only changes when cycling
  through software types. Only redraw when the label actually changes.

- The clear area for the list content extended into the scroll bar
  region, causing it to be erased and redrawn on each scroll. Reduce
  the clear width to stop before the scroll bar (SOFTWARE_PANEL_W - 16
  instead of - 3).

- Move cycle button initial drawing to draw_software_panel() to ensure
  it's visible on first display, since update_software_list() now skips
  redrawing when the label hasn't changed.

Additionally, adjust column positions for better spacing:
- Location column: 130 -> 126
- Address column:  204 -> 200
- Version column:  290 -> 284

Author: reinauer

src/gui.c

@@ -793,6 +793,12 @@ static void draw_software_panel(void)
                SOFTWARE_PANEL_W - 2, 14,
 	       get_string(MSG_SYSTEM_SOFTWARE));
 
+    /* Draw cycle button initially */
+    Button *cycle_btn = find_button(BTN_SOFTWARE_CYCLE);
+    if (cycle_btn) {
+        draw_cycle_button(cycle_btn);
+    }
+
     update_software_list();
 }
 
@@ -825,21 +831,24 @@ static void update_software_list(void)
             return;
     }
 
-    /* Clear list area */
+    /* Clear list area (stop before scroll bar at -14) */
     SetAPen(rp, COLOR_PANEL_BG);
     RectFill(rp, SOFTWARE_PANEL_X + 2, list_top - 7,
-             SOFTWARE_PANEL_X + SOFTWARE_PANEL_W - 3,
+             SOFTWARE_PANEL_X + SOFTWARE_PANEL_W - 16,
              list_top + list_height - 5);
 
-    /* Update cycle button */
+    /* Update cycle button only if label changed */
     Button *cycle_btn = find_button(BTN_SOFTWARE_CYCLE);
     if (cycle_btn) {
-        cycle_btn->label = app->software_type == SOFTWARE_LIBRARIES ?
-                               get_string(MSG_LIBRARIES) :
-                           app->software_type == SOFTWARE_DEVICES ?
-                               get_string(MSG_DEVICES) :
-                               get_string(MSG_RESOURCES);
-        draw_cycle_button(cycle_btn);
+        const char *new_label = app->software_type == SOFTWARE_LIBRARIES ?
+                                    get_string(MSG_LIBRARIES) :
+                                app->software_type == SOFTWARE_DEVICES ?
+                                    get_string(MSG_DEVICES) :
+                                    get_string(MSG_RESOURCES);
+        if (cycle_btn->label != new_label) {
+            cycle_btn->label = new_label;
+            draw_cycle_button(cycle_btn);
+        }
     }
 
     /* Draw scroll arrows with triangles */
@@ -880,18 +889,18 @@ static void update_software_list(void)
 
         /* Location */
         snprintf(buffer, 12, "%-10s", get_location_string(entry->location));
-        Move(rp, SOFTWARE_PANEL_X + 130, y);
+        Move(rp, SOFTWARE_PANEL_X + 126, y);
         Text(rp, (CONST_STRPTR)buffer, strlen(buffer));
 
         /* Address */
         snprintf(buffer, 12, "$%08lX", (unsigned long)entry->address);
         SetAPen(rp, COLOR_HIGHLIGHT);
-        Move(rp, SOFTWARE_PANEL_X + 204, y);
+        Move(rp, SOFTWARE_PANEL_X + 200, y);
         Text(rp, (CONST_STRPTR)buffer, strlen(buffer));
 
         /* Version */
         snprintf(buffer, sizeof(buffer), "V%d.%d", entry->version, entry->revision);
-        Move(rp, SOFTWARE_PANEL_X + 290, y);
+        Move(rp, SOFTWARE_PANEL_X + 284, y);
         Text(rp, (CONST_STRPTR)buffer, strlen(buffer));
 
         y += 8;