brev/launch-nemoclaw.sh: pin PLUGIN_REF and COMMUNITY_REF to stable tags instead of main

Start with brev/launch-nemoclaw.sh and verify the available tags and branch backing the public launchable, noting that OpenShell-Community currently has no tag to use. Coordinate creation of a stable community tag, then update the script defaults to the matching community and NemoClaw tags; this is done when deployments no longer default to main and future release-time bumps are defined.

Problem

brev/launch-nemoclaw.sh on feat/brev-nemoclaw-plugin defaults both refs to main:

# line 22
COMMUNITY_REF="${COMMUNITY_REF:-${COMMUNITY_BRANCH:-main}}"
# line 26
PLUGIN_REF="${PLUGIN_REF:-main}"

The public NVIDIA Brev launchable (build.nvidia.com/nemoclaw → Try Early Preview) runs this script on every deploy. Tracking main means each user gets whatever HEAD is at that moment — behavior drifts, regressions ship silently to end users, and reproducing a bug report is impossible without a commit SHA.

Reported upstream in NVIDIA/NemoClaw#1242 by NV QA.

Constraint

• NVIDIA/NemoClaw has git tags (latest v0.0.18) — PLUGIN_REF can pin to one today.
• NVIDIA/OpenShell-Community has no tags and no releases — COMMUNITY_REF has nothing to pin to yet. Cutting a stable tag here is a prerequisite.

Proposed fix

1. Cut a stable tag on feat/brev-nemoclaw-plugin (or the branch backing the public launchable) — e.g. brev-launchable-v0.0.18 matching NemoClaw's release.
2. Update defaults in brev/launch-nemoclaw.sh:

   COMMUNITY_REF="${COMMUNITY_REF:-brev-launchable-v0.0.18}"
   PLUGIN_REF="${PLUGIN_REF:-v0.0.18}"
   

3. Release-time bump — tie PLUGIN_REF updates to NemoClaw release cadence so the launchable always points at the latest stable pair.

Environment

• Script: https://raw.githubusercontent.com/NVIDIA/OpenShell-Community/feat/brev-nemoclaw-plugin/brev/launch-nemoclaw.sh
• Launchable: https://brev.nvidia.com/launchable/deploy/now?launchableID=env-3Azt0aYgVNFEuz7opyx3gscmowS
• Related: NVIDIA/NemoClaw#1242