feat(cli): add enterprise external-workspaces CLI command (#19287)

This pull request introduces support for external workspace management, allowing users to register and manage workspaces that are provisioned and managed outside of the Coder.

* coder external-workspaces create - Creates a new external workspace (this command extends coder create)
  * Example: coder external-workspaces create ext-workspace --template=externally-managed-workspace -y
  * Checks if template has coder_external_agent resource before creating a workspace
* coder external-workspaces list - Lists all external workspaces
* coder external-workspaces agent-instructions <workspace name> <agent name> - Retrieves agent connection instruction
  * Example: coder external-workspaces agent-instructions ext-workspace main --output=json

docs/reference/cli/external-workspaces_create.md

@@ -0,0 +1,128 @@
+<!-- DO NOT EDIT | GENERATED CONTENT -->
+# external-workspaces create
+
+Create a new external workspace
+
+## Usage
+
+```console
+coder external-workspaces create [flags] [workspace]
+```
+
+## Description
+
+```console
+  - Create a workspace for another user (if you have permission):
+
+     $ coder create <username>/<workspace_name>
+```
+
+## Options
+
+### -t, --template
+
+|             |                                   |
+|-------------|-----------------------------------|
+| Type        | <code>string</code>               |
+| Environment | <code>$CODER_TEMPLATE_NAME</code> |
+
+Specify a template name.
+
+### --template-version
+
+|             |                                      |
+|-------------|--------------------------------------|
+| Type        | <code>string</code>                  |
+| Environment | <code>$CODER_TEMPLATE_VERSION</code> |
+
+Specify a template version name.
+
+### --preset
+
+|             |                                 |
+|-------------|---------------------------------|
+| Type        | <code>string</code>             |
+| Environment | <code>$CODER_PRESET_NAME</code> |
+
+Specify the name of a template version preset. Use 'none' to explicitly indicate that no preset should be used.
+
+### --start-at
+
+|             |                                        |
+|-------------|----------------------------------------|
+| Type        | <code>string</code>                    |
+| Environment | <code>$CODER_WORKSPACE_START_AT</code> |
+
+Specify the workspace autostart schedule. Check coder schedule start --help for the syntax.
+
+### --stop-after
+
+|             |                                          |
+|-------------|------------------------------------------|
+| Type        | <code>duration</code>                    |
+| Environment | <code>$CODER_WORKSPACE_STOP_AFTER</code> |
+
+Specify a duration after which the workspace should shut down (e.g. 8h).
+
+### --automatic-updates
+
+|             |                                                 |
+|-------------|-------------------------------------------------|
+| Type        | <code>string</code>                             |
+| Environment | <code>$CODER_WORKSPACE_AUTOMATIC_UPDATES</code> |
+| Default     | <code>never</code>                              |
+
+Specify automatic updates setting for the workspace (accepts 'always' or 'never').
+
+### --copy-parameters-from
+
+|             |                                                    |
+|-------------|----------------------------------------------------|
+| Type        | <code>string</code>                                |
+| Environment | <code>$CODER_WORKSPACE_COPY_PARAMETERS_FROM</code> |
+
+Specify the source workspace name to copy parameters from.
+
+### -y, --yes
+
+|      |                   |
+|------|-------------------|
+| Type | <code>bool</code> |
+
+Bypass prompts.
+
+### --parameter
+
+|             |                                    |
+|-------------|------------------------------------|
+| Type        | <code>string-array</code>          |
+| Environment | <code>$CODER_RICH_PARAMETER</code> |
+
+Rich parameter value in the format "name=value".
+
+### --rich-parameter-file
+
+|             |                                         |
+|-------------|-----------------------------------------|
+| Type        | <code>string</code>                     |
+| Environment | <code>$CODER_RICH_PARAMETER_FILE</code> |
+
+Specify a file path with values for rich parameters defined in the template. The file should be in YAML format, containing key-value pairs for the parameters.
+
+### --parameter-default
+
+|             |                                            |
+|-------------|--------------------------------------------|
+| Type        | <code>string-array</code>                  |
+| Environment | <code>$CODER_RICH_PARAMETER_DEFAULT</code> |
+
+Rich parameter default values in the format "name=value".
+
+### -O, --org
+
+|             |                                  |
+|-------------|----------------------------------|
+| Type        | <code>string</code>              |
+| Environment | <code>$CODER_ORGANIZATION</code> |
+
+Select which organization (uuid or name) to use.