Event gateway Resources which omit secrets in response show drift when plain strings are used as input

[harshadixit12]

For example, konnect_event_gateway_static_key accepts value as an expression, as well as base64 encoded string.
However, the API does not return the value in response body if it is a plain string.
Terraform interprets this as missing value, and tries to update in subsequent plan/apply.

Since API returns value when it is an expression, no false drift is seen in that case.
https://kongstrong.slack.com/archives/C089Z3BMC9Z/p1766080688569839?thread_ts=1765403226.115999&cid=C089Z3BMC9Z

[TT1228]

This is also the same case when updating schema registry with a plain password in authentication. Terraform plan return this error

│ Error: Incorrect attribute value type
│
│   on schema_registry_sensitive_aware_update.tf line 3, in resource "konnect_event_gateway_schema_registry" "my_eventgatewayschemaregistry":
│    3:   confluent = {
│    4:     config = {
│    5:       authentication = {
│    6:         basic = {
│    7:           username = "a"
│    8:         }
│    9:       }
│   10:       endpoint = "a.com:8080"
│   11:       schema_type = "avro"
│   12:       timeout_seconds = 10
│   13:     }
│   14:     created_at = "2025-12-19T08:18:48.408177Z"
│   15:     id = "019b35b0-a76e-7a71-9cf5-bb77d867c0e5"
│   16:     name = "asaa"
│   17:     updated_at = "2025-12-19T08:18:48.408177Z"
│   18:   }
│
│ Inappropriate value for attribute "confluent": attribute "config": attribute "authentication": attribute "basic": attribute "password" is required.

I think we need to run through all SensitiveDataAwareScheme in event gateway to make sure that terraform can resolve this pattern

[harshadixit12]

We can evaluate making these fields write-only
https://kongstrong.slack.com/archives/C07AQH7SAF8/p1769150663613759
cc: @shivaygupta-dotcom