RDKEMW-17667 : Add timezone getter method and onTimeZoneChanged event

[swethasukumarr]

No description provided.

[Copilot]

Pull request overview

Adds timezone support to the Firebolt Localization module by introducing a new read-only timeZone getter and a corresponding onTimeZoneChanged subscription event, with implementation and OpenRPC/test coverage updates to keep the API surface consistent across the SDK.

Changes:

• Added ILocalization::timeZone() getter and ILocalization::subscribeOnTimeZoneChanged(...) event subscription API.
• Implemented the new getter and subscription in LocalizationImpl.
• Updated unit/component tests and OpenRPC specs to cover the new method/event and validate payload handling.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
test/unit/localizationTest.cpp	Adds unit tests for timeZone() success/failure and subscribing to onTimeZoneChanged.
test/component/localizationTest.cpp	Adds component tests for timeZone() and validates event delivery vs. invalid payloads.
src/localization_impl.h	Extends LocalizationImpl interface with timeZone() and subscribeOnTimeZoneChanged(...).
src/localization_impl.cpp	Implements timeZone() getter and onTimeZoneChanged subscription wiring.
include/firebolt/localization.h	Extends public ILocalization API with the new getter and subscription method + docs.
docs/openrpc/the-spec/firebolt-open-rpc.json	Adds OpenRPC entries for Localization.timeZone and Localization.onTimeZoneChanged.
docs/openrpc/openrpc/localization.json	Adds module-level OpenRPC entry for timeZone.