fix, feat, doc: massive build system refactorion, bug fixes and apex documentation (#19)

services/docs/content/en/apex/reference/_index.md

@@ -0,0 +1,20 @@
+---
+title: Reference
+description: CLI, actions, environment variables, and the engine API.
+weight: 30
+---
+
+Technical reference for the apex fleet-operations framework surface: the command-line interface, the built-in [actions](/apex/glossary#action), the environment contract they consume, and the Python [engine](/apex/glossary#engine) API.
+
+{{% cards %}}
+{{< card link="cli" title="CLI reference" icon="terminal" subtitle="Command-line invocation, subcommands, and exit codes." >}}
+{{< card link="actions" title="Actions reference" icon="play" subtitle="Built-in actions and their arguments." >}}
+{{< card link="environment" title="Environment reference" icon="variable" subtitle="Environment variables exposed to actions and compositions." >}}
+{{< card link="engine-api" title="Engine API reference" icon="code" subtitle="Python modules that power the engine." >}}
+{{% /cards %}}
+
+---
+
+**See also:**
+
+- [GitHub: apex.ermnvldmr.com](https://github.com/deytenit/apex.ermnvldmr.com)