docs: update references to renamed commons repository (#11)

services/docs/content/en/root/guides/action-development.md

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+---
+title: Action development
+description: Developing atomic automation tasks in the Root framework.
+weight: 30
+---
+
+[Actions](/root/glossary#action) are atomic automation tasks. Following the "Stupid Action" philosophy, they must remain declarative and rely on the library for complex operations.
+
+## Creating a new action {#create}
+
+{{% steps %}}
+
+### Step 1: Create the script file
+
+Place your script in `scripts/actions/{group}/{name}`. Do not use file extensions.
+
+### Step 2: Implement metadata
+
+Every action must provide a description and argument list for the help system.
+
+```bash filename="scripts/actions/utils/my-action"
+action_metadata() {
+  cat <<EOF
+description: "Brief summary of the task."
+args:
+  - NODE: "The node name"
+  - PARAM: "A custom parameter"
+EOF
+}
+```
+
+### Step 3: Initialize context
+
+Use the `root_require_node` helper to establish the environment. This must be the first functional step in your script.
+
+```bash filename="scripts/actions/utils/my-action"
+root_require_node "${1:-}"
+shift
+```
+
+### Step 4: Use namespaced helpers
+
+Perform operations using the `root_*` library functions. Rely on `ROOT_` environment variables for all pathing.
+
+```bash filename="scripts/actions/utils/my-action"
+root_log_info "Processing node $ROOT_NODE"
+root_sys_restart_service "my-service"
+```
+
+{{% /steps %}}
+
+## Library namespaces {#libraries}
+
+Actions have access to the following modules:
+
+- `root_core_*`: Logging and Telegram notifications.
+- `root_init_*`: Declarative service initialization and package management.
+- `root_sys_*`: Systemd and unit file management.
+- `root_template_*`: Envsubst-based rendering and configuration injection.
+- `root_validate_*`: Input, file, and OS validation.
+
+---
+
+**See also:**
+
+- [Reference: ROOT_ API reference](/root/reference/root-api)
+- [Concept: Infrastructure architecture](/root/concepts/architecture)