FINERACT-2244: migrate Floating Rates to CommandDispatcher

[aditinikam]

Migrate the Floating Rate module write path off the legacy CommandWrapperBuilder -> logCommandSource -> @CommandType (JsonCommand) pipeline onto the typed CommandDispatcher (CQRS) infrastructure, fully JsonCommand-free.

• API resource injects CommandDispatcher and dispatches typed FloatingRate{Create,Update}Command, returning typed responses.
• New typed FloatingRateWriteService + command handlers; FloatingRate domain createNew/update and FloatingRateDataValidator retyped to operate on the request DTOs (locale-aware date parsing via DateTimeFormatter).
• SecurityConfig gains POST/PUT /floatingrates matchers (CREATE/UPDATE) since the logCommandSource permission check is gone; read endpoints and FloatingRatesReadPlatformService are left untouched.
• Removed legacy FloatingRateWritePlatformService, @CommandType handlers, and the CommandWrapperBuilder floating-rate methods.
• fineract-rates now depends on :fineract-command.

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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