Claiming namespace [spline]

### Namespace

spline

### Ownership

- [x] The namespace is not currently owned on Open VSX (verify by a search on [open-vsx.org](https://open-vsx.org))

### Account Age

- [x] The GitHub ID making this request has at least 12 months of public history

### VS Code Publisher with Repo

- [ ] The namespace is also a publisher account on the VS Code Marketplace (check by browsing https://marketplace.visualstudio.com/publishers/{publisher}) and has an extension published there with a repo specified in its package.json file.

### VS Code Publisher without Repo

- [x] The namespace is also a publisher account on the VS Code Marketplace and does not have published extensions or has published extensions with no GitHub repos.

### Not a VS Code Marketplace Publisher

- [ ] The namespace is not a publisher account on the VS Code Marketplace

### All Other Cases

- [ ] You are unable to provide the inputs required in the three options above. This option will take the longest to process.

### Claim evidence

VS Code Marketplace publisher: https://marketplace.visualstudio.com/publishers/spline
Extension: spline.spline — https://marketplace.visualstudio.com/items?itemName=spline.spline
Open VSX: https://open-vsx.org/extension/spline/spline

Option 2 applies rather than Option 1 because the extension's package.json
carries no repository field — the source lives in a private monorepo
(github.com/splinetool), so there is no public repo URL to cite.

Reader access has been granted to Open VSX administrator ID
9f9ebf84-37d2-648b-bef8-8af4132d803a on the Marketplace publisher account, and
will be revoked once this issue is closed.

The namespace corresponds to Spline (spline.design), the company that publishes
the extension.

Start by checking the Open VSX namespace page and the VS Code Marketplace publisher and extension links listed in the issue, then verify the namespace ownership checklist and reader access evidence. Done means the claim is validated and the spline namespace is assigned or the issue is closed with a decision.

Written by the indexing model from the issue text.