BUG: "An error occurred, please try again" After Google Sign-In

### Is there an existing issue for this?

- [x] I have searched the existing issues

### What happened?

## 📌 Issue Overview
When a user(patient) clicks "Continue with Google", they first receive a green pop-up message:
✅ "Signed in as FirstName LastName"
This indicates that Google Sign-In was successful.

However, immediately afterward, they receive a red pop-up message:
❌ "An error occurred, please try again."

After debugging, we discovered that the root cause of this error was the patient table missing in Supabase deployment.

## 🔍 Steps to Reproduce

1. Open the Flutter Patient app.
2. Click "Continue with Google".
3. Observe the green pop-up confirming successful sign-in.
4. Observe the red pop-up with the error message.
5. Check the Flutter logs for the Supabase relation "public.patient" does not exist error.

## 🎯 Expected Behavior

- After signing in with Google, a user should be redirected to the appropriate screen (home or personal details).
- No error should be shown if authentication is successful.
- If a new user signs in for the first time, their patient record should be created automatically.

## 🚨 Actual Behavior

1. User clicks "Continue with Google".
2. Google authentication succeeds (green pop-up).
3. The app attempts to check if the user exists in the patient table.
4. API call fails because the patient table does not exist in Supabase.
5. A generic error is shown (red pop-up: "An error occurred, please try again").

The Flutter logs show the following error:
```
I/flutter (21358): Error checking patient existence:
PostgrestException(message: {"code":"42P01","details":null,"hint":null,"message":"relation \"public.patient\" does not exist"},
code: 404, details: Not Found, hint: null)
```
🔹 This confirms that Supabase is rejecting queries because the patient table is missing.

## 💡 Suggested Improvements

Automatically Create the patient Table via Supabase Migrations.

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