Initial CV-aligned infrastructure portfolio

Rework portfolio around Linux operations, Zabbix monitoring, migration validation, and ELK/Grafana log observability.

Add AAP-style LVM resize workflow, Zabbix server/proxy/agent automation assets, Linux/AIX monitoring templates, and updated validation CI.

docs/architecture.md

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+# Architecture Overview
+
+## Portfolio Shape
+
+This repository is organized around professional infrastructure work that maps to the CV:
+
+```text
+professional-infra/
+  linux-operations-automation/
+  zabbix-monitoring-incident-response/
+  migration-validation-framework/
+  log-observability-elk-grafana/
+
+devops-labs/
+  future side projects only when ready
+```
+
+## Project Roles
+
+### Linux Operations Automation
+
+Operational automation for Linux server work:
+
+- provisioning and baseline configuration,
+- patching and hardening,
+- service/failure simulation,
+- AAP-style LVM filesystem resize workflow with before/after evidence.
+
+### Zabbix Monitoring + Incident Response
+
+Simple checks and OS monitoring:
+
+- Zabbix server/proxy/agent automation structure,
+- active and passive proxy design,
+- Linux and AIX monitoring templates,
+- maintenance and incident response runbooks.
+
+### Migration Validation Framework
+
+Evidence tooling for platform/storage migrations:
+
+- before/after snapshot collection,
+- drift detection,
+- risk assessment,
+- JSON and HTML reports.
+
+### Log Observability ELK/Grafana
+
+Log monitoring and incident evidence:
+
+- Filebeat ingestion,
+- Logstash parsing,
+- Elasticsearch storage,
+- Kibana/Grafana review surfaces,
+- incident log simulation.
+
+## Design Principles
+
+- Keep implemented work separate from roadmap ideas.
+- Prefer reviewable automation and evidence over overbuilt local labs.
+- Make every project independently validatable.
+- Treat Zabbix and ELK/Grafana as complementary monitoring tools:
+  - Zabbix for simple checks and OS health,
+  - ELK/Grafana for logs and observability evidence.