docs: rename INDEX.md to index.md and update display name

- Renamed root INDEX.md to index.md (lowercase)
- Changed navigation title from "Documentation Index" to "Index"
- Removed caps lock for cleaner appearance

docs/contributing/contributing.md

@@ -31,5 +31,5 @@ We welcome contributions! Please see our [Development Guide](DEVELOPMENT.md) for
 
 ---
 
-**Looking for user documentation?** See the [User Portal](../user/INDEX.md)
-**Need API docs?** See the [Developer Portal](../developer/INDEX.md)
+**Looking for user documentation?** See the [User Portal](../user/user-guide.md)
+**Need API docs?** See the [Developer Portal](../developer/development.md)

docs/developer/api-reference.md

@@ -1,7 +1,7 @@
 # Bookhoard API Reference
 
 > **⚠️ Legacy Document**: This is a monolithic API reference (1,600+ lines).
-> For updated, split endpoint documentation with interactive API explorer, see [API Documentation Portal](api/INDEX.md).
+> For updated, split endpoint documentation with interactive API explorer, see [API Documentation Portal](api/api-reference.md).
 >
 > **Use the split docs for:**
 > - Easier navigation by category

docs/developer/development.md

@@ -23,7 +23,7 @@ Welcome to the Bookhoard developer documentation. This section contains API refe
 
 Browse individual endpoint documentation with interactive API Explorer:
 
-- **[API Documentation](api/INDEX.md)** - Split endpoint docs
+- **[API Documentation](api/api-reference.md)** - Split endpoint docs
   - [Authentication](api/authentication/) - Register, login, tokens
   - [Users](api/users/) - Profile management
   - [Libraries](api/libraries/) - Library operations
@@ -73,5 +73,5 @@ Browse individual endpoint documentation with interactive API Explorer:
 
 ---
 
-**Looking for user documentation?** See the [User Portal](../user/INDEX.md)
-**Need to deploy?** See the [Operations Portal](../operations/INDEX.md)
+**Looking for user documentation?** See the [User Portal](../user/user-guide.md)
+**Need to deploy?** See the [Operations Portal](../operations/operations.md)

docs/operations/operations.md

@@ -30,5 +30,5 @@ Welcome to the Bookhoard operations documentation. This section contains guides
 
 ---
 
-**Looking for user documentation?** See the [User Portal](../user/INDEX.md)
-**Need API docs?** See the [Developer Portal](../developer/INDEX.md)
+**Looking for user documentation?** See the [User Portal](../user/user-guide.md)
+**Need API docs?** See the [Developer Portal](../developer/development.md)

docs/user/user-guide.md

@@ -49,4 +49,4 @@ Learn how to configure your e-reader devices to sync with Bookhoard:
 
 ---
 
-**Looking for developer documentation?** See the [Developer Portal](../developer/INDEX.md)
+**Looking for developer documentation?** See the [Developer Portal](../developer/development.md)