Remove registration page and redirect home to timeline

Remove the registration UI page completely and use the public timeline as the default start page.

Changes:
- Delete auth/register.html template
- Remove /register route from AuthViewController
- Update HomeController to redirect / to /timeline
- Remove /register from public paths list in auth.js

Users will no longer see a registration option in the UI. Registration can only be done via direct API calls if enabled.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/main/java/org/operaton/fitpub/controller/AuthViewController.java

@@ -15,11 +15,6 @@ public class AuthViewController {
         return "auth/login";
     }
 
-    @GetMapping("/register")
-    public String register() {
-        return "auth/register";
-    }
-
     @PostMapping("/logout")
     public String logout() {
         // Logout is handled client-side (removing JWT token)

src/main/java/org/operaton/fitpub/controller/HomeController.java

@@ -11,6 +11,6 @@ public class HomeController {
 
     @GetMapping("/")
     public String home() {
-        return "index";
+        return "redirect:/timeline";
     }
 }