Adds code to warn users, when scope is downgraded

[AltamashShaikh]

Description

Adds code to wanr users, when scope is downgraded

Issue No

Steps to Replicate the Issue

1. Edit an existing OAuth client with admin access
2. Change the scope to read and notice no notification on downgrade informing exiting token will keep working till the TTL
3. Checkout this PR and perform same step and now it should show a warning

Checklist

• [✔] Tested locally or on demo2/demo3?
• [✔] New test case added/updated?
• [✔] Are all newly added texts included via translation?
• [✔] Are text sanitized properly? (Eg use of v-text v/s v-html for vue)
• [✔] Version bumped?
• [✔] I have understood, reviewed, and tested all AI outputs before use
• [✔] All AI instructions respect security, IP, and privacy rules
• [NA] Documentation updated?