FINERACT-2436: Fix Client Trends by Week or Month don't work on Postgresql

[Kengne-yvana]

Description

Describe the changes made and why they were made. (Ignore if these details are present on the associated Apache Fineract JIRA ticket.)

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[Kengne-yvana]

This change is to make sure FINERACT uses postgresql and MySQL when needed without breaking the code . Having the same author and path but different id. I added database-specific Liquibase contexts to ensure the correct SQL dialect is applied without affecting existing MySQL installations. This fix replaces MySQL-specific functions (WEEK, MONTHNAME) with ISO-standard functions (EXTRACT, TO_CHAR) for PostgreSQL environments, while maintaining the same author and file path for traceability.

[galovics]

Whats the reason for changing an existing changelog file?

[Kengne-yvana]

@galovics I choose to add the fix to this file because that's where my research let me to which is where the reports where updated for Mysql .

[IOhacker]

@Kengne-yvana I think that it is better to create a new changelog file. So then the fix will be applied as a new migration.