chore: add Axiom env vars to .env.docker

Add AXIOM_TOKEN and AXIOM_DATASET configuration. Mark UPTRACE_DSN
as deprecated but keep for rollback.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: AchoArnold

api/.env.docker

@@ -55,10 +55,15 @@ REDIS_URL=redis://@redis:6379
 # Google Cloud Storage bucket for MMS attachments. Leave empty to use in-memory storage.
 GCS_BUCKET_NAME=
 
-# [optional] If you would like to use uptrace.dev for distributed tracing, you can set the DSN here.
-# This is optional and you can leave it empty if you don't want to use uptrace
+# [deprecated] Uptrace DSN - kept for rollback. Use AXIOM_TOKEN/AXIOM_DATASET instead.
 UPTRACE_DSN=
 
+# Axiom observability configuration
+# API token for Axiom (required for logging, traces, and metrics in production)
+AXIOM_TOKEN=
+# Dataset name in Axiom where logs, traces, and metrics are sent
+AXIOM_DATASET=
+
 
 # [optional] Websocket configuration for https://pusher.com if you will like to frontend to update in real time
 PUSHER_APP_ID=