feat(auth): add username field to user schema and authentication process

- Updated user schema to include a unique username field.
- Modified authentication logic to support sign-in using either email or username.
- Enhanced sign-up process to require a username and validate its uniqueness.
- Updated login and profile routes to reflect changes in user identification.
- Adjusted frontend forms to accommodate username input alongside email.

drizzle/meta/_journal.json

@@ -64,6 +64,13 @@
       "when": 1772821532270,
       "tag": "0008_skinny_warpath",
       "breakpoints": true
+    },
+    {
+      "idx": 9,
+      "version": "6",
+      "when": 1772822823122,
+      "tag": "0009_true_gravity",
+      "breakpoints": true
     }
   ]
 }