Implement handling of setUiHints action "set_invocation_effect_parameters"

Specifically handles "is_invocation_effect_enabled" parameter to set enabled status of invocation effect.

Invocation effect is set to default true for now, we'll update this to be false once Gemini has a solution for calling setUiHints on our dogfood population.

Bug: 405328848
Flag: com.android.systemui.shared.enable_lpp_assist_invocation_effect
Test: Manual testing that an assistant can enable/disable the effect using setUiHints

Change-Id: Ic72a53c216e4a23d94d19f1d7d5c639f977717fd