merge: resolve merge conflicts with main branch and update student toolkit

backend/src/main/resources/application.properties

@@ -1,9 +1,7 @@
 # ─── DATABASE CONNECTION CONFIGURATION ───
 spring.datasource.url=jdbc:postgresql://localhost:5432/rit_freshers_hub?sslmode=disable
 spring.datasource.username=postgres
-
-spring.datasource.password=Anbukathir@#$2006
-
+spring.datasource.password=${DB_PASSWORD:Anbukathir@#$2006}
 
 # ─── JPA / HIBERNATE SETTINGS ───
 spring.jpa.database-platform=org.hibernate.dialect.PostgreSQLDialect