fix(title): 预设4项修复—间距0.5px+删tooltip+描边对齐+背景淡化

1. generate.css: gap 1.5px→0.5px, 卡片背景 #3a3a3a→#404040, hover/active→#4d4d4d
2. TitlePresetsGrid.tsx: 删除 title={p.label} tooltip
3. constants.ts: previewStyle 的描边与 style.stroke 对齐
   - classic_white/variety_show 保留描边（stroke=true）
   - 其余6个preset删除 _strokeColor/_strokeWidth（stroke=false）
   预览T字效果与实际标题完全一致

apps/web/src/pages/generate/components/title/TitlePresetsGrid.tsx

@@ -87,7 +87,6 @@ const TitlePresetsGrid: React.FC<TitlePresetsGridProps> = ({
             key={p.key}
             className={`xx-title-preset-card${isActive ? " active" : ""}`}
             onClick={() => onApply(p.key)}
-            title={p.label}
           >
             <span className="xx-title-preset-preview-text" style={{ position: "relative" }}>
               {/* 底层：描边轮廓 */}

apps/web/src/pages/generate/constants.ts

@@ -91,8 +91,6 @@ export const TITLE_PRESETS = [
     style: { size: 32, color: "#d4a843", bold: true, italic: false, stroke: false, shadow: true },
     previewStyle: {
       color: "#d4a843",
-      _strokeColor: "#1a1000",
-      _strokeWidth: 1.5,
       fontWeight: 700,
       fontSize: "32px",
       textShadow: "1px 1px 3px rgba(0,0,0,0.8)",
@@ -104,8 +102,6 @@ export const TITLE_PRESETS = [
     style: { size: 24, color: "#333333", bold: false, italic: false, stroke: false, shadow: false },
     previewStyle: {
       color: "#e8e8e8",
-      _strokeColor: "#cccccc",
-      _strokeWidth: 1,
       fontWeight: 400,
       fontSize: "32px",
     },
@@ -129,8 +125,6 @@ export const TITLE_PRESETS = [
     style: { size: 24, color: "#1a1a1a", bold: false, italic: false, stroke: false, shadow: false },
     previewStyle: {
       color: "#e0e0e0",
-      _strokeColor: "#bbbbbb",
-      _strokeWidth: 1,
       fontWeight: 400,
       fontSize: "32px",
     },
@@ -141,8 +135,6 @@ export const TITLE_PRESETS = [
     style: { size: 28, color: "#e8d5b7", bold: false, italic: false, stroke: false, shadow: true },
     previewStyle: {
       color: "#e8d5b7",
-      _strokeColor: "#3a2a1a",
-      _strokeWidth: 1.5,
       fontWeight: 400,
       fontSize: "32px",
       textShadow: "2px 2px 6px rgba(0,0,0,0.7)",
@@ -154,8 +146,6 @@ export const TITLE_PRESETS = [
     style: { size: 32, color: "#00e5ff", bold: true, italic: false, stroke: false, shadow: true },
     previewStyle: {
       color: "#00e5ff",
-      _strokeColor: "#00e5ff",
-      _strokeWidth: 1,
       fontWeight: 700,
       fontSize: "32px",
       textShadow: "0 0 4px #00e5ff, 0 0 8px #00e5ff, 0 0 16px rgba(0,229,255,0.5)",
@@ -167,8 +157,6 @@ export const TITLE_PRESETS = [
     style: { size: 28, color: "#333333", bold: false, italic: false, stroke: false, shadow: true },
     previewStyle: {
       color: "#e0e0e0",
-      _strokeColor: "#cccccc",
-      _strokeWidth: 1,
       fontWeight: 400,
       fontSize: "32px",
       textShadow: "1px 1px 2px rgba(0,0,0,0.3)",

apps/web/src/pages/generate/generate.css

@@ -1734,7 +1734,7 @@
 .xx-title-presets-grid {
   display: grid;
   grid-template-columns: repeat(8, 1fr);
-  gap: 1.5px;
+  gap: 0.5px;
 }
 
 .xx-title-preset-card {
@@ -1744,7 +1744,7 @@
   width: 48px;
   height: 48px;
   padding: 0;
-  background: #3a3a3a;
+  background: #404040;
   border: 2px solid transparent;
   border-radius: 8px;
   cursor: pointer;
@@ -1753,12 +1753,12 @@
 
 .xx-title-preset-card:hover {
   border-color: #666;
-  background: #4a4a4a;
+  background: #4d4d4d;
 }
 
 .xx-title-preset-card.active {
   border-color: #409eff;
-  background: #4a4a4a;
+  background: #4d4d4d;
 }
 
 .xx-title-preset-preview-text {