chore: try loki as logging solution

knowledge base/loki.md

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+# Grafana Loki
+
+Horizontally scalable, highly available, multi-tenant log aggregation system inspired by Prometheus and designed to be
+very cost-effective and easy to operate.
+
+1. [TL;DR](#tldr)
+1. [Further readings](#further-readings)
+   1. [Sources](#sources)
+
+## TL;DR
+
+It indexes **a set of labels** for each log stream instead of the full logs' contents.
+
+Needs agents or other clients to push logs to the server.
+
+Supports object storage solutions.
+
+<details>
+  <summary>Setup</summary>
+
+```sh
+# Install via package repository.
+apt install 'loki'
+dnf install 'loki'
+
+# Run via Docker.
+docker run --name loki -d \
+  -p '3100:3100' -v "$(pwd)/config/loki.yml:/etc/loki/config.yml:ro" \
+  'grafana/loki:3.3.2' -config.file='/etc/loki/config.yml'
+```
+
+Default configuration file for package-based installations is `/etc/loki/config.yml`.
+
+</details>
+
+<details>
+  <summary>Usage</summary>
+
+```sh
+# Check the server is working
+curl 'http://loki.fqdn:3100/ready'
+curl 'http://loki.fqdn:3100/metrics'
+```
+
+</details>
+
+## Further readings
+
+- [Website]
+- [Codebase]
+- [Grafana]
+- [Promtail]
+
+### Sources
+
+- [Documentation]
+- [HTTP API reference]
+
+<!--
+  Reference
+  ═╬═Time══
+  -->
+
+<!-- In-article sections -->
+<!-- Knowledge base -->
+[grafana]: grafana.md
+[promtail]: promtail.md
+
+<!-- Files -->
+<!-- Upstream -->
+[codebase]: https://github.com/grafana/loki
+[documentation]: https://grafana.com/docs/loki/latest/
+[http api reference]: https://grafana.com/docs/loki/latest/reference/loki-http-api/
+[website]: https://grafana.com/oss/loki/
+
+<!-- Others -->