Create `fireworks-msa` branch for KV-outer integration PR

Request

Please create an integration branch fireworks-msa on this repo (from current main) so we can open a PR into fireworks-msa rather than directly into main.

Maintainer one-liner

git fetch origin main
git push origin origin/main:refs/heads/fireworks-msa

Or in the GitHub UI: Branches → New branch → name fireworks-msa, source main.

Follow-up PR (after branch exists)

From fork ipiszy/MSA branch fireworks-msa (2 commits on top of main):

gh pr create -R MiniMax-AI/MSA \
  --base fireworks-msa \
  --head ipiszy:fireworks-msa \
  --title "Integrate Fireworks KV-outer sparse prefill" \
  --body-file ...

Compare link (works once fireworks-msa exists on upstream):

https://github.com/MiniMax-AI/MSA/compare/fireworks-msa...ipiszy:fireworks-msa?expand=1

Context

• Fork: https://github.com/ipiszy/MSA (fireworks-msa branch)
• Vendored from fw-ai/minimax-kernels
• Previously opened as PR #7 against main (closed; wrong target branch)

Create the upstream fireworks-msa branch from the current main branch using the listed Git command or GitHub's Branches → New branch flow. Confirm that fireworks-msa exists and is based on main; the follow-up PR from ipiszy/MSA can then target it instead of main.