Duplicate env var error leaks the env value into logs #3070

If a template or Run request has two env vars with the same name, validation fails and the error text includes the whole entry as JSON, value and all:

env[1]: Duplicate value: {"name":"API_KEY","value":"sk-..."}

The RPC interceptors log this error at Info on the "Handle RPC" line. The error is already a plain string by the time it's logged, so the logging handler's proto redaction can't mask it. The secret ends up in the logs, even though the request in the same log record correctly shows value:"[REDACTED]".

How to reproduce

Send a Run request (or create a template) with:

env: [{name: API_KEY, value: sk-secret}, {name: API_KEY, value: sk-secret}]

Then check the "Handle RPC" log line. sk-secret is in the error text.

Expected

The error still names the duplicate (API_KEY), but shows value:"[REDACTED]".