Add new indexing strategy to support case insensitivity

[Sachin-Mamoru]

Proposed changes in this pull request

• Implement Indexing and Optimization Enhancements for Improved Database Performance product-is#21662

When should this PR be merged

• Check migration impact if we drop primary keys. Else we can auto-generate a primary key.
• And if a foreign key references the primary key what should be the process to drop it?
• Check the impact of the unique constrain and unique index possibility of having null values
• Add specific migration docs for these changes
• Newly added index checks the usage of queries and analyses the order and all

CREATE INDEX IDX_UU_LO_UI_UUN_TI ON UM_USER(UM_ID,LOWER(UM_USER_NAME),UM_TENANT_ID);