perf: make module loading synchronous, flip right panel layout

- Remove unnecessary async/await from loadModules (static imports)
- Move game controls to top of right panel
- Move preview header below controls, above preview
- Flip inset shadow to top of preview section

src/index.html

@@ -60,18 +60,6 @@
 
 				<!-- Right Panel: Preview + Navigation -->
 				<div class="right-panel">
-					<div class="preview-section">
-						<div class="preview-wrapper">
-							<div class="preview-frame" id="preview-area"></div>
-							<div class="expected-overlay" id="expected-overlay">
-								<div class="expected-frame" id="preview-expected"></div>
-							</div>
-						</div>
-						<div class="preview-header">
-							<span class="preview-label" data-i18n="yourOutput">Your Output</span>
-							<button id="show-expected-btn" class="btn btn-small" data-i18n="showExpected">Show Expected</button>
-						</div>
-					</div>
 					<div class="game-controls">
 						<button id="prev-btn" class="btn" data-i18n="previous">Previous</button>
 						<span class="module-pill" id="module-pill">
@@ -80,6 +68,18 @@
 						</span>
 						<button id="next-btn" class="btn btn-primary" data-i18n="next">Next</button>
 					</div>
+					<div class="preview-section">
+						<div class="preview-header">
+							<span class="preview-label" data-i18n="yourOutput">Your Output</span>
+							<button id="show-expected-btn" class="btn btn-small" data-i18n="showExpected">Show Expected</button>
+						</div>
+						<div class="preview-wrapper">
+							<div class="preview-frame" id="preview-area"></div>
+							<div class="expected-overlay" id="expected-overlay">
+								<div class="expected-frame" id="preview-expected"></div>
+							</div>
+						</div>
+					</div>
 				</div>
 			</main>