The project form gets «Crear en TaskStream» while the project has no
board, and `taskstream: true` on a PATCH does the same through the API.
A refusal leaves the edit unsaved; a project with a board keeps it, and
`taskstream_key` without the flag is still ignored.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
`taskstream: true` on POST /v1/projects also creates the project in
TaskStream, public, as the caller (their Pireon token is passed on), and
the answer carries `taskstream_key` and `taskstream_url`. The key is
`taskstream_key` or one made from the default-language slug.
The board is opened before the project is saved: if TaskStream refuses
it, nothing is created here and the reason comes back as a validation
error (502 when TaskStream does not answer). Machine tokens need the
server's own TASKSTREAM_TOKEN. Updates ignore the flag, and duplicates do
not inherit the link.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
