Grant the project creator an owner role on creation

[silentsudo-io]

Fixes #659.

The problem

add_project() never grants the creator a role, so a new project ends up with no rows in project_member at all. Two consequences:

1. Sharing is broken. With no roles on the project, the Collaborators page has nothing to work with and the owner cannot add anyone — including themselves. This was the presenting symptom on our self-hosted CE server.
2. With GLOBAL_ADMIN=True, the creator cannot see their own project. GlobalWorkspaceHandler.get_user_role() returns GUEST for non-superusers, and a GUEST reaches a project only via project_member or Project.public. So projects_query(ProjectPermissions.Read) filters the project out before the flag=created creator test is reached — GET /v1/project/paginated?flag=created returns count=0 for the user who just created it.

The change

p.set_role(current_user.id, ProjectRole.OWNER) before the commit, in both creation paths:

• add_project()
• clone_project() — same omission, same effect on a cloned project

ProjectRole was already imported in the module, so this adds no imports. set_role() appends to the project_users relationship, which cascades on commit, so it works on the still-pending Project.

Notes for reviewers

• set_role() fires project_access_granted. It will now fire for the creator on every project creation. That seemed semantically right — access was granted — but if you would rather not emit it for the creator, say so and I will restructure.
• Existing servers stay broken without a migration. Projects already created carry no project_member rows. A data migration granting owner to creator_id where a project has no members would repair them. Happy to add one to this PR if you want it here rather than separately.
• I have not added a test. If you would like one, point me at the preferred place and I will follow up.

Verified against

Reproduced on self-hosted CE, backend image 2025.7.3, single global workspace, GLOBAL_* all at defaults. Two projects created by two different users via two different paths (web UI and REST API) both landed with zero member rows. add_project() is structurally unchanged from 2025.7.3 through 2026.6.2, so this affects all of them.

CLA: I have added silentsudo-io to the individual CLA list in LICENSES/CLA-signed-list.md in this PR.