Fix Tab component usage in quick-start guides

Remove unsupported Tabs/Tab components and use simple section headers instead. Build now completes successfully.

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

content/docs/quick-start/backend-developers.mdx

@@ -19,9 +19,7 @@ Object Definition → Everything Auto-Generated
 
 ## Quick Comparison
 
-<Tabs items={['Traditional (Express + Sequelize)', 'ObjectStack Protocol']}>
-
-<Tab value="Traditional (Express + Sequelize)">
+### Traditional Approach (Express + Sequelize)
 
 ```typescript
 // 1. Define Model
@@ -49,9 +47,7 @@ const validateTask = (req, res, next) => {
 // Total: 4 files, ~150 lines of code
 ```
 
-</Tab>
-
-<Tab value="ObjectStack Protocol">
+### ObjectStack Protocol
 
 ```typescript
 // Everything in ONE definition
@@ -79,10 +75,6 @@ export const Task = ObjectSchema.create({
 // Total: 1 file, ~15 lines of code
 ```
 
-</Tab>
-
-</Tabs>
-
 ## Field Types You Know and Love
 
 ObjectStack provides **23+ field types** with automatic validation:

content/docs/quick-start/frontend-developers.mdx

@@ -16,9 +16,7 @@ ObjectStack: Define UI JSON → Instant Update (no rebuild!)
 
 ## Quick Comparison
 
-<Tabs items={['Traditional React', 'ObjectStack Protocol']}>
-
-<Tab value="Traditional React">
+### Traditional React
 
 ```tsx
 // 1. Build data grid component
@@ -71,9 +69,7 @@ function TaskForm({ taskId }) {
 // Total: 2 components, ~100 lines of code
 ```
 
-</Tab>
-
-<Tab value="ObjectStack Protocol">
+### ObjectStack Protocol
 
 ```typescript
 // Define UI as JSON - Renderer handles everything
@@ -113,10 +109,6 @@ export const TaskFormView = FormView.create({
 // ✅ Loading/Error states handled automatically
 ```
 
-</Tab>
-
-</Tabs>
-
 ## View Types
 
 ObjectStack provides **5 pre-built view types**: