feat: add module definition completeness validation and permissions

Add new validation rules MOD-020 to MOD-023 for module definition
completeness and standardize permissions across all modules.

Changes:
- Add MOD-020: Module definitions must have required attributes
- Add MOD-021: Modules with menus should have features
- Add MOD-022: Feature modules should have permissions
- Add MOD-023: Modules with routers should use get_*_with_routers pattern

Module permissions added:
- analytics: view, export, manage_dashboards
- billing: view_tiers, manage_tiers, view_subscriptions, manage_subscriptions, view_invoices
- cart: view, manage
- checkout: view_settings, manage_settings
- cms: view_pages, manage_pages, view_media, manage_media, manage_themes
- loyalty: view_programs, manage_programs, view_rewards, manage_rewards
- marketplace: view_integration, manage_integration, sync_products
- messaging: view_messages, send_messages, manage_templates
- payments: view_gateways, manage_gateways, view_transactions

Module improvements:
- Complete cart module with features and permissions
- Complete checkout module with features and permissions
- Add features to catalog module
- Add version to cms module
- Fix loyalty platform_router attachment
- Add path definitions to payments module
- Remove empty scheduled_tasks from dev_tools module

Documentation:
- Update module-system.md with new validation rules
- Update architecture-rules.md with MOD-020 to MOD-023

Tests:
- Add unit tests for module definition completeness
- Add tests for permission structure validation

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

static/platform/css/tailwind.css

@@ -0,0 +1,287 @@
+/* static/platform/css/tailwind.css */
+/* Tailwind CSS v4 source file for Platform frontend */
+/* CSS-first configuration - no tailwind.config.js needed */
+
+@import "tailwindcss";
+
+/* Content sources for tree-shaking */
+@source "../../../app/templates/platform/**/*.html";
+@source "../../../app/templates/shared/**/*.html";
+@source "../js/**/*.js";
+
+/* ==========================================================================
+   THEME CONFIGURATION
+   Migrated from legacy tailwind.config.js with Windmill color palette
+   ========================================================================== */
+
+@theme {
+    /* Font Family - Inter as primary sans-serif */
+    --font-sans: 'Inter', ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
+
+    /* ==========================================================================
+       COLOR PALETTE
+       Custom colors from Windmill/Flowbite design system
+       ========================================================================== */
+
+    /* Gray - Custom darker palette */
+    --color-gray-50: #f9fafb;
+    --color-gray-100: #f4f5f7;
+    --color-gray-200: #e5e7eb;
+    --color-gray-300: #d5d6d7;
+    --color-gray-400: #9e9e9e;
+    --color-gray-500: #707275;
+    --color-gray-600: #4c4f52;
+    --color-gray-700: #24262d;
+    --color-gray-800: #1a1c23;
+    --color-gray-900: #121317;
+
+    /* Cool Gray */
+    --color-cool-gray-50: #fbfdfe;
+    --color-cool-gray-100: #f1f5f9;
+    --color-cool-gray-200: #e2e8f0;
+    --color-cool-gray-300: #cfd8e3;
+    --color-cool-gray-400: #97a6ba;
+    --color-cool-gray-500: #64748b;
+    --color-cool-gray-600: #475569;
+    --color-cool-gray-700: #364152;
+    --color-cool-gray-800: #27303f;
+    --color-cool-gray-900: #1a202e;
+
+    /* Red */
+    --color-red-50: #fdf2f2;
+    --color-red-100: #fde8e8;
+    --color-red-200: #fbd5d5;
+    --color-red-300: #f8b4b4;
+    --color-red-400: #f98080;
+    --color-red-500: #f05252;
+    --color-red-600: #e02424;
+    --color-red-700: #c81e1e;
+    --color-red-800: #9b1c1c;
+    --color-red-900: #771d1d;
+
+    /* Orange */
+    --color-orange-50: #fff8f1;
+    --color-orange-100: #feecdc;
+    --color-orange-200: #fcd9bd;
+    --color-orange-300: #fdba8c;
+    --color-orange-400: #ff8a4c;
+    --color-orange-500: #ff5a1f;
+    --color-orange-600: #d03801;
+    --color-orange-700: #b43403;
+    --color-orange-800: #8a2c0d;
+    --color-orange-900: #771d1d;
+
+    /* Yellow */
+    --color-yellow-50: #fdfdea;
+    --color-yellow-100: #fdf6b2;
+    --color-yellow-200: #fce96a;
+    --color-yellow-300: #faca15;
+    --color-yellow-400: #e3a008;
+    --color-yellow-500: #c27803;
+    --color-yellow-600: #9f580a;
+    --color-yellow-700: #8e4b10;
+    --color-yellow-800: #723b13;
+    --color-yellow-900: #633112;
+
+    /* Green */
+    --color-green-50: #f3faf7;
+    --color-green-100: #def7ec;
+    --color-green-200: #bcf0da;
+    --color-green-300: #84e1bc;
+    --color-green-400: #31c48d;
+    --color-green-500: #0e9f6e;
+    --color-green-600: #057a55;
+    --color-green-700: #046c4e;
+    --color-green-800: #03543f;
+    --color-green-900: #014737;
+
+    /* Teal */
+    --color-teal-50: #edfafa;
+    --color-teal-100: #d5f5f6;
+    --color-teal-200: #afecef;
+    --color-teal-300: #7edce2;
+    --color-teal-400: #16bdca;
+    --color-teal-500: #0694a2;
+    --color-teal-600: #047481;
+    --color-teal-700: #036672;
+    --color-teal-800: #05505c;
+    --color-teal-900: #014451;
+
+    /* Blue */
+    --color-blue-50: #ebf5ff;
+    --color-blue-100: #e1effe;
+    --color-blue-200: #c3ddfd;
+    --color-blue-300: #a4cafe;
+    --color-blue-400: #76a9fa;
+    --color-blue-500: #3f83f8;
+    --color-blue-600: #1c64f2;
+    --color-blue-700: #1a56db;
+    --color-blue-800: #1e429f;
+    --color-blue-900: #233876;
+
+    /* Indigo */
+    --color-indigo-50: #f0f5ff;
+    --color-indigo-100: #e5edff;
+    --color-indigo-200: #cddbfe;
+    --color-indigo-300: #b4c6fc;
+    --color-indigo-400: #8da2fb;
+    --color-indigo-500: #6875f5;
+    --color-indigo-600: #5850ec;
+    --color-indigo-700: #5145cd;
+    --color-indigo-800: #42389d;
+    --color-indigo-900: #362f78;
+
+    /* Purple */
+    --color-purple-50: #f6f5ff;
+    --color-purple-100: #edebfe;
+    --color-purple-200: #dcd7fe;
+    --color-purple-300: #cabffd;
+    --color-purple-400: #ac94fa;
+    --color-purple-500: #9061f9;
+    --color-purple-600: #7e3af2;
+    --color-purple-700: #6c2bd9;
+    --color-purple-800: #5521b5;
+    --color-purple-900: #4a1d96;
+
+    /* Pink */
+    --color-pink-50: #fdf2f8;
+    --color-pink-100: #fce8f3;
+    --color-pink-200: #fad1e8;
+    --color-pink-300: #f8b4d9;
+    --color-pink-400: #f17eb8;
+    --color-pink-500: #e74694;
+    --color-pink-600: #d61f69;
+    --color-pink-700: #bf125d;
+    --color-pink-800: #99154b;
+    --color-pink-900: #751a3d;
+
+    /* Extended max-height */
+    --max-height-xl: 36rem;
+}
+
+/* ==========================================================================
+   DARK MODE VARIANT
+   Matches the .dark class pattern used in templates
+   ========================================================================== */
+
+@variant dark (&:where(.dark, .dark *));
+
+/* ==========================================================================
+   CUSTOM UTILITIES
+   Shadow outline utilities (migrated from plugin)
+   ========================================================================== */
+
+@utility shadow-outline-gray {
+    box-shadow: 0 0 0 3px hsla(0, 0%, 84%, 0.45);
+}
+
+@utility shadow-outline-red {
+    box-shadow: 0 0 0 3px hsla(0, 90%, 84%, 0.45);
+}
+
+@utility shadow-outline-orange {
+    box-shadow: 0 0 0 3px hsla(24, 97%, 77%, 0.45);
+}
+
+@utility shadow-outline-yellow {
+    box-shadow: 0 0 0 3px hsla(45, 97%, 53%, 0.45);
+}
+
+@utility shadow-outline-green {
+    box-shadow: 0 0 0 3px hsla(156, 70%, 70%, 0.45);
+}
+
+@utility shadow-outline-teal {
+    box-shadow: 0 0 0 3px hsla(183, 71%, 69%, 0.45);
+}
+
+@utility shadow-outline-blue {
+    box-shadow: 0 0 0 3px hsla(214, 95%, 84%, 0.45);
+}
+
+@utility shadow-outline-indigo {
+    box-shadow: 0 0 0 3px hsla(227, 94%, 85%, 0.45);
+}
+
+@utility shadow-outline-purple {
+    box-shadow: 0 0 0 3px hsla(259, 97%, 87%, 0.45);
+}
+
+@utility shadow-outline-pink {
+    box-shadow: 0 0 0 3px hsla(327, 87%, 84%, 0.45);
+}
+
+/* ==========================================================================
+   FORM STYLES
+   Custom form placeholder styling (replaces @tailwindcss/custom-forms)
+   ========================================================================== */
+
+@layer base {
+    input::placeholder,
+    textarea::placeholder {
+        color: var(--color-gray-400);
+    }
+}
+
+/* ==========================================================================
+   PLATFORM-SPECIFIC COMPONENTS
+   ========================================================================== */
+
+@layer components {
+    /* Gradient backgrounds */
+    .gradient-primary {
+        background: linear-gradient(135deg, var(--color-indigo-500) 0%, var(--color-purple-500) 100%);
+    }
+
+    .gradient-accent {
+        background: linear-gradient(135deg, var(--color-purple-500) 0%, var(--color-pink-500) 100%);
+    }
+
+    /* Primary button */
+    .btn-primary {
+        background-color: var(--color-indigo-500);
+        color: white;
+        padding: 0.75rem 1.5rem;
+        border-radius: 0.5rem;
+        font-weight: 600;
+        transition: all 0.2s;
+    }
+
+    .btn-primary:hover {
+        opacity: 0.9;
+        transform: translateY(-1px);
+    }
+
+    /* Secondary button */
+    .btn-secondary {
+        background-color: var(--color-gray-100);
+        color: var(--color-gray-700);
+        padding: 0.75rem 1.5rem;
+        border-radius: 0.5rem;
+        font-weight: 600;
+        transition: all 0.2s;
+    }
+
+    .dark .btn-secondary {
+        background-color: var(--color-gray-700);
+        color: var(--color-gray-100);
+    }
+
+    .btn-secondary:hover {
+        background-color: var(--color-gray-200);
+    }
+
+    .dark .btn-secondary:hover {
+        background-color: var(--color-gray-600);
+    }
+
+    /* Card hover effect */
+    .card-hover {
+        transition: all 0.3s ease;
+    }
+
+    .card-hover:hover {
+        transform: translateY(-4px);
+        box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
+    }
+}