docs(reference): experimental flags table omits the openclaw flag

docs/src/content/docs/reference/experimental.md says at line 21 that the command will "List every registered flag with its current state", and the "Available flags" table at line 168 is that list. The table has 8 rows. FLAGS in src/apm_cli/core/experimental.py:57 registers 9.

The missing one is openclaw, at experimental.py:128, described as "Deploy skills to OpenClaw agent runtime directories." Its hint points at --target openclaw and --target openclaw --global. Since it gates a real deploy target, someone reading the reference page to find out how to turn it on will not find it there.

The other eight line up exactly — verbose_version, copilot_cowork, copilot_app, grok_cloud, marketplace_authoring, registries, canvas, external_scanners — each rendered kebab-case in the table.

I checked today's CLI consistency report (#2985), which covers help-text wording and not this, and no open PR touches the file, out of 59 examined.

Happy to send the one-row addition if that is welcome.

Compare the Available flags table in docs/src/content/docs/reference/experimental.md with FLAGS in src/apm_cli/core/experimental.py, starting at the openclaw entry around line 128. Confirm the existing rows' kebab-case naming and the openclaw hint, then update the reference so all nine registered flags are represented, including its deployment-target description.