feat(images): 添加图片分辨率检测与自动压缩功能

- 增加图片分辨率检测，提示用户图片超过2K分辨率
- 对大于2K分辨率图片进行自动缩放压缩，确保宽高不超过2048
- 在生成Base64时保持图片原格式，非PNG格式转为JPEG并设定压缩质量为0.9
- 优化上传流程，避免因大图影响性能和加载速度
- 提示文字及状态更新，提升用户体验

static/js/main.js

@@ -373,6 +373,22 @@ function handleNewFiles(files) {
     const newFiles = Array.from(files).filter(f => f.type.startsWith('image/'));
     if (newFiles.length === 0) return;
 
+    // 检查分辨率并提示压缩
+    let largeFound = false;
+    Promise.all(newFiles.map(file => new Promise(resolve => {
+        const url = URL.createObjectURL(file);
+        const img = new Image();
+        img.onload = () => {
+            if (img.width > 2048 || img.height > 2048) largeFound = true;
+            URL.revokeObjectURL(url);
+            resolve();
+        };
+        img.onerror = resolve;
+        img.src = url;
+    }))).then(() => {
+        if (largeFound) showToast('检测到图片分辨率大于 2K，将为您自动压缩至 2K 分辨率', 'info');
+    });
+
     // 如果处于设置器模式，严格限制为 1 张
     if (isSetterActive) {
         if (newFiles.length > 0) {
@@ -505,16 +521,51 @@ document.getElementById('submitBtn').onclick = async () => {
     try {
         let image_data = [];
 
-        // 1. 将图片转换为 Base64
+        // 1. 将图片转换为 Base64 (并压缩过大图片)
         if (uploadedFiles.length > 0) {
             btnText.innerText = "正在准备图片数据...";
-            const readFileAsBase64 = (file) => new Promise((resolve, reject) => {
+            const processImageFile = (file) => new Promise((resolve, reject) => {
                 const reader = new FileReader();
-                reader.onload = () => resolve(reader.result);
+                reader.onload = (e) => {
+                    const img = new Image();
+                    img.onload = () => {
+                        const maxDim = 2048;
+                        let w = img.width;
+                        let h = img.height;
+
+                        if (w <= maxDim && h <= maxDim) {
+                            resolve(e.target.result);
+                            return;
+                        }
+
+                        if (w > h) {
+                            if (w > maxDim) {
+                                h = Math.round(h * (maxDim / w));
+                                w = maxDim;
+                            }
+                        } else {
+                            if (h > maxDim) {
+                                w = Math.round(w * (maxDim / h));
+                                h = maxDim;
+                            }
+                        }
+
+                        const canvas = document.createElement('canvas');
+                        canvas.width = w;
+                        canvas.height = h;
+                        const ctx = canvas.getContext('2d');
+                        ctx.drawImage(img, 0, 0, w, h);
+                        // 保持原格式，如果不是 png 则默认 jpeg (0.9 质量)
+                        const outType = file.type === 'image/png' ? 'image/png' : 'image/jpeg';
+                        resolve(canvas.toDataURL(outType, 0.9));
+                    };
+                    img.onerror = reject;
+                    img.src = e.target.result;
+                };
                 reader.onerror = reject;
                 reader.readAsDataURL(file);
             });
-            image_data = await Promise.all(uploadedFiles.map(f => readFileAsBase64(f)));
+            image_data = await Promise.all(uploadedFiles.map(f => processImageFile(f)));
         }
 
         // 2. 并行启动多个生成任务