To give users in the project.group_project_user group edit permissions on a project if they are the project manager (i.e., if they are listed as the user_id of the project), you will need to adjust your security rules carefully.
Step 1: Create a Record Rule for the Project User Group
You need to define a record rule that grants write access to users only on projects where they are the manager (user_id).
Step 2: Modify the Access Control List (ACL) if Necessary
The existing ACL for project.group_project_user grants only read access. Since you want to allow write access based on a condition, ensure that the ACL for the project.group_project_user group
The ir.rule you added applies a filter to the project.project model, only granting write permissions (perm_write) where the user_id matches the current user's ID - user.id
This rule only applies to users in the project.group_project_user group, allowing them to edit their own projects while keeping the default read-only permissions for other projects.