ci: configure and stabilize CI/CD pipeline

- fix runner configuration issues
- correct workflow labels and execution environment
- resolve dependency issues in pipeline (python deps)
- improve reliability of automation runs

observability-stack/scenarios/incident_simulation.md

@@ -0,0 +1,21 @@
+# Scenario: Incident Simulation
+
+## Description
+
+Generate a controlled application and infrastructure incident so the logging pipeline, alert rules, and dashboards can be reviewed with realistic event timing.
+
+## Commands
+
+```bash
+cd observability-stack
+docker compose config
+./scenarios/incident_simulation.sh comprehensive
+tail -n 40 logs/incident_simulation.log
+```
+
+## Expected Result
+
+- The compose file validates successfully.
+- The simulation writes a sequence of CPU, memory, service, database, and application error events.
+- Alert examples indicate firing and resolved states.
+- Operators can trace incident progression through logs and dashboard queries.