v1.2.9 — printer safety, FTPS compatibility, and Blender MCP

Bambu uploads now retain the printer host identity across FTPS channels, fixing the Node 22/24 wrapped-socket session regression, and use TLS 1.2 for reliable session reuse. Raw print operations enforce the model guard; upload scratch paths prevent overwriting or deleting unrelated local files.

The release ports standard Blender MCP discovery, tool forwarding, and verified STL edits while preserving legacy bridge compatibility. STL validation uses bounded memory and honors edit deadlines and cancellation. It also refreshes dependencies, fixes package-version reporting, builds npm artifacts from source, and adds CI and Docker checks.

Validation: 64 tests, Node 18/20/22/24 CI, clean npm installation of all entrypoints, and Docker initialization. Generated editing scripts passed in isolated Blender 5.0.1. Physical X1C validation remains outstanding; no printer commands were sent. The local Blender addon was inactive during the live connection probe.

Includes the previously unpublished fixes from main versions 1.2.6–1.2.8. See PR #23 and CHANGELOG.md for details.