feat(webui): add Tailwind build system and refactor frontend architecture

- Replace Tailwind CDN with local build (PostCSS + autoprefixer + daisyui)

- Add CSS build scripts with automatic prepare hook on npm install

- Create account-actions.js service layer with unified response format

- Extend ErrorHandler.withLoading() for automatic loading state management

- Add skeleton screens for initial load, silent refresh for subsequent updates

- Implement loading animations for async operations (buttons, modals)

- Improve empty states and add ARIA labels for accessibility

- Abstract component styles using @apply (buttons, badges, inputs)

- Add JSDoc documentation for Dashboard modules

- Update README and CLAUDE.md with development guidelines

public/views/settings.html

@@ -2,7 +2,7 @@
     activeTab: 'ui'
 }" class="view-container">
     <!-- Header & Tabs -->
-    <div class="glass-panel rounded-xl border border-space-border flex flex-col overflow-hidden">
+    <div class="view-card !p-0 flex flex-col overflow-hidden">
         <div class="bg-space-900/50 border-b border-space-border px-8 pt-8 pb-0 shrink-0">
             <div class="flex items-center justify-between mb-6">
                 <h3 class="text-xl font-bold text-white flex items-center gap-2">
@@ -558,7 +558,7 @@
                 </div>
 
                 <!-- Models List -->
-                <div class="glass-panel rounded-lg overflow-hidden">
+                <div class="view-card !p-0">
                     <table class="standard-table">
                         <thead>
                             <tr>
@@ -609,7 +609,7 @@
                                                 placeholder="e.g. claude-sonnet-4-5 or gemini-3-flash"
                                                 @keydown.enter="await updateModelConfig(modelId, { mapping: newMapping }); stopEditing()"
                                                 @keydown.escape="newMapping = config.mapping || ''; stopEditing()">
-                                            <button class="btn btn-xs btn-ghost btn-square text-green-500 hover:bg-green-500/20"
+                                            <button class="btn-action-success"
                                                 @click="await updateModelConfig(modelId, { mapping: newMapping }); stopEditing()"
                                                 title="Save">
                                                 <svg xmlns="http://www.w3.org/2000/svg" class="w-3.5 h-3.5" fill="none"
@@ -618,7 +618,7 @@
                                                         stroke-width="2" d="M5 13l4 4L19 7" />
                                                 </svg>
                                             </button>
-                                            <button class="btn btn-xs btn-ghost btn-square text-gray-500 hover:bg-gray-500/20"
+                                            <button class="btn-action-neutral"
                                                 @click="newMapping = config.mapping || ''; stopEditing()"
                                                 title="Cancel">
                                                 <svg xmlns="http://www.w3.org/2000/svg" class="w-3.5 h-3.5" fill="none"
@@ -628,7 +628,7 @@
                                                 </svg>
                                             </button>
                                             <button x-show="config.mapping"
-                                                    class="btn btn-xs btn-ghost btn-square text-red-400 hover:bg-red-500/20"
+                                                    class="btn-action-danger"
                                                     @click="await updateModelConfig(modelId, { mapping: '' }); stopEditing()"
                                                     title="Clear mapping">
                                                 <svg xmlns="http://www.w3.org/2000/svg" class="w-3.5 h-3.5" fill="none"
@@ -700,7 +700,7 @@
             <div x-show="activeTab === 'server'" x-data="window.Components.serverConfig()"
                 class="space-y-6 max-w-2xl animate-fade-in pb-10">
                 <!-- 🔐 Security Section -->
-                <div class="glass-panel p-6 border border-neon-yellow/20 bg-neon-yellow/5">
+                <div class="view-card border-neon-yellow/20 bg-neon-yellow/5">
                     <div class="flex items-center justify-between">
                         <div class="flex items-center gap-4">
                             <div
@@ -741,7 +741,7 @@
 
                     <!-- Debug Mode -->
                     <div
-                        class="form-control glass-panel p-4 border border-space-border/50 hover:border-neon-purple/50 transition-all">
+                        class="form-control view-card border-space-border/50 hover:border-neon-purple/50">
                         <div class="flex items-center justify-between">
                             <div class="flex flex-col gap-1">
                                 <span class="text-sm font-medium text-gray-200"
@@ -763,7 +763,7 @@
 
                     <!-- Token Cache -->
                     <div
-                        class="form-control glass-panel p-4 border border-space-border/50 hover:border-neon-green/50 transition-all">
+                        class="form-control view-card border-space-border/50 hover:border-neon-green/50">
                         <div class="flex items-center justify-between">
                             <div class="flex flex-col gap-1">
                                 <span class="text-sm font-medium text-gray-200"
@@ -787,7 +787,7 @@
                 </div>
 
                 <!-- ▼ Advanced Tuning (Fixed Logic) -->
-                <div class="glass-panel border border-space-border/50 overflow-hidden">
+                <div class="view-card !p-0 border-space-border/50">
                     <div class="flex items-center justify-between p-4 cursor-pointer hover:bg-white/5 transition-colors"
                         @click="advancedExpanded = !advancedExpanded">
                         <div class="flex items-center gap-3">