feat: update image import instructions for mobile users to enhance usability

Author: cs-util

README.md

@@ -74,7 +74,7 @@
 
 ## 4) Image handling
 
-* **Import**: Camera (`<input type="file" accept="image/*" capture="environment">`) or gallery.
+* **Import**: Native file picker (`<input type="file" accept="image/*">`) lets mobile users capture a new photo or pull one from their gallery without leaving the flow.
 * **Orientation**: Apply EXIF orientation, then **strip EXIF** (privacy).
 * **Storage**: **Only optimized display** version, long edge ≈ **4096 px**, **WebP/AVIF** (JPEG fallback), sRGB.
 * **Max per map**: 25–50 MB (config). Oversize → auto-downscale + toast.

index.html

@@ -61,9 +61,9 @@ <h2 class="text-2xl font-semibold text-slate-100">Import map photo</h2>
                     <p class="text-sm text-slate-300">Choose a sharp, well-lit image of your trailboard or printed map. Snap2Map keeps only an optimized copy on your device.</p>
                     <label class="block w-full">
                       <span class="sr-only">Upload map image</span>
-                      <input id="mapImageInput" type="file" accept="image/*" capture="environment" class="block w-full text-sm text-slate-200 file:mr-4 file:py-2 file:px-4 file:rounded-lg file:border-0 file:text-sm file:font-semibold file:bg-blue-600 file:text-white hover:file:bg-blue-500">
+                      <input id="mapImageInput" type="file" accept="image/*" class="block w-full text-sm text-slate-200 file:mr-4 file:py-2 file:px-4 file:rounded-lg file:border-0 file:text-sm file:font-semibold file:bg-blue-600 file:text-white hover:file:bg-blue-500">
                     </label>
-                    <p class="text-xs text-slate-400">Tip: On mobile you can snap a picture directly using your camera.</p>
+                    <p class="text-xs text-slate-400">Tip: Mobile browsers let you take a new photo or pick one from your gallery when you tap the button above.</p>
                   </div>
                 </div>
                 <div id="photoMap" class="h-full w-full min-h-[55vh] sm:min-h-[60vh] lg:min-h-[65vh]"></div>