[FEATURE] Tag connector events with source, service_call and execution_mode dimensions

[gopikrishna000]

Feature Description

Connector events emitted to ClickHouse (connector_events) currently can't be attributed to who made the call, what kind of call it was, or whether it was the real or a shadow execution. As Hyperswitch routes traffic through the Unified Connector Service (UCS) — including shadow mode where a direct call and a UCS call run side by side — we need to distinguish these legs in analytics.

Proposal

Add three low-cardinality dimensions to every connector event:

column	values	meaning
source	hyperswitch / ucs	which service emitted the event
call_type	connector / service	the call to the payment connector vs a request at the UCS service interface
execution_mode	primary / shadow	real execution vs shadow mirror

call_type is a leg label — orthogonal to source and caller/transport-agnostic, so it stays correct regardless of caller or transport. execution_mode is the two-state observability projection of the routing ExecutionMode (NotApplicable = Direct = a live leg → primary).

Expected tagging

scenario	events (source / call_type / execution_mode)
Direct	hyperswitch / connector / primary
UCS primary	hyperswitch / service / primary · ucs / service / primary · ucs / connector / primary
Shadow — direct leg	hyperswitch / connector / primary
Shadow — UCS leg	hyperswitch / service / shadow · ucs / service / shadow · ucs / connector / shadow

The UCS side emits matching field names (with call_type derived from its EventStage) so both producers land in the same connector_events table.

Scope

• Add the fields to ConnectorEvent and populate them at the direct connector path and the UCS gRPC path (including the shadow leg).
• Add the matching LowCardinality(String) columns to the connector_events ClickHouse tables and materialized views.