Scene.set() JS lifecycle, UI sprite caching, emulator test scripts

- Add Scene.set(module) so JerryScript can switch scenes via
  require()'d {init, update, dispose} modules; wire it into
  engineUpdate() and rework overworldscene.js/init.js to the new shape.
- Fix scriptManagerExecFile() never pushing its own file's directory
  onto the require() dir stack, breaking relative require() calls from
  a top-level entry script (e.g. init.js -> ./overworldscene.js).
- Cache sprite geometry across frames for uislider/uitab/uiframe
  (dialogs/textbox/settings) and give uitextbox a per-page glyph cache
  instead of one spriteBatchBuffer call per visible character. uiconsole
  drops its alloc/free vertex buffer for a fixed-size one. uifps skips
  rebuilding its label when the text hasn't changed.
- Add PSP_OPTIMIZATION_PLAN.md and a handful of UI/spritebatch unit
  tests covering the new caching logic.
- Add Dolphin/PPSSPP emulator smoke-test scripts (+ Docker variants and
  CI jobs) for GameCube/Wii/PSP.

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

test/display/CMakeLists.txt

@@ -6,4 +6,5 @@
 include(dusktest)
 
 # Tests
-dusktest(test_color.c)
+dusktest(test_color.c)
+dusktest(test_spritebatchsprite.c)

test/display/test_spritebatchsprite.c

@@ -0,0 +1,92 @@
+/**
+ * Copyright (c) 2026 Dominic Masters
+ *
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "dusktest.h"
+#include "display/spritebatch/spritebatchsprite.h"
+
+static void test_spriteBatchSpriteTilesetPosition_create(void **state) {
+  tileset_t tileset = {
+    .tileWidth = 8,
+    .tileHeight = 8,
+    .tileCount = 4,
+    .columns = 2,
+    .rows = 2,
+    .uv = { 0.5f, 0.5f }
+  };
+
+  spritebatchsprite_t sprite = spriteBatchSpriteTilesetPosition(
+    &tileset, 1, 1, 10.0f, 20.0f, 8.0f, 8.0f
+  );
+
+  assert_float_equal(sprite.min[0], 10.0f, 0.0001f);
+  assert_float_equal(sprite.min[1], 20.0f, 0.0001f);
+  assert_float_equal(sprite.min[2], 0.0f, 0.0001f);
+  assert_float_equal(sprite.max[0], 18.0f, 0.0001f);
+  assert_float_equal(sprite.max[1], 28.0f, 0.0001f);
+  assert_float_equal(sprite.uvMin[0], 0.5f, 0.0001f);
+  assert_float_equal(sprite.uvMin[1], 0.5f, 0.0001f);
+  assert_float_equal(sprite.uvMax[0], 1.0f, 0.0001f);
+  assert_float_equal(sprite.uvMax[1], 1.0f, 0.0001f);
+}
+
+static void test_spriteBatchSpriteTilesetPosition_zeroSize(void **state) {
+  tileset_t tileset = {
+    .tileWidth = 8,
+    .tileHeight = 8,
+    .tileCount = 1,
+    .columns = 1,
+    .rows = 1,
+    .uv = { 1.0f, 1.0f }
+  };
+
+  spritebatchsprite_t sprite = spriteBatchSpriteTilesetPosition(
+    &tileset, 0, 0, 10.0f, 20.0f, 0.0f, 8.0f
+  );
+
+  assert_float_equal(sprite.min[0], 0.0f, 0.0001f);
+  assert_float_equal(sprite.min[1], 0.0f, 0.0001f);
+  assert_float_equal(sprite.max[0], 0.0f, 0.0001f);
+  assert_float_equal(sprite.max[1], 0.0f, 0.0001f);
+}
+
+static void test_spriteBatchSpriteTranslate(void **state) {
+  spritebatchsprite_t sprite = {
+    .min = { 1.0f, 2.0f, 0.0f },
+    .max = { 5.0f, 6.0f, 0.0f },
+    .uvMin = { 0.25f, 0.5f },
+    .uvMax = { 0.75f, 1.0f }
+  };
+
+  spritebatchsprite_t translated = spriteBatchSpriteTranslate(
+    &sprite, 10.0f, -3.0f
+  );
+
+  assert_float_equal(translated.min[0], 11.0f, 0.0001f);
+  assert_float_equal(translated.min[1], -1.0f, 0.0001f);
+  assert_float_equal(translated.max[0], 15.0f, 0.0001f);
+  assert_float_equal(translated.max[1], 3.0f, 0.0001f);
+
+  // UVs must be untouched by translation.
+  assert_float_equal(translated.uvMin[0], 0.25f, 0.0001f);
+  assert_float_equal(translated.uvMin[1], 0.5f, 0.0001f);
+  assert_float_equal(translated.uvMax[0], 0.75f, 0.0001f);
+  assert_float_equal(translated.uvMax[1], 1.0f, 0.0001f);
+
+  // Original sprite must be untouched.
+  assert_float_equal(sprite.min[0], 1.0f, 0.0001f);
+  assert_float_equal(sprite.min[1], 2.0f, 0.0001f);
+}
+
+int main(int argc, char **argv) {
+  const struct CMUnitTest tests[] = {
+    cmocka_unit_test(test_spriteBatchSpriteTilesetPosition_create),
+    cmocka_unit_test(test_spriteBatchSpriteTilesetPosition_zeroSize),
+    cmocka_unit_test(test_spriteBatchSpriteTranslate),
+  };
+
+  return cmocka_run_group_tests(tests, NULL, NULL);
+}