users: Rework users management based on experience for improved UI/UX

Add invite-only onboarding and user management CLI

- add invite/accept flows with JWT tokens and email templates
- introduce usermanager helper script with multi-instance config
- update docs for invite-only flow and CLI usage
- add tests for invites and event handling tweaks

Signed-off-by: Denys Fedoryshchenko <denys.f@collabora.com>

Author: nuclearcat

README.md

@@ -31,6 +31,11 @@ Generate a new key for [Authentication](https://docs.kernelci.org/api_pipeline/a
 After that, please refer to [create and add a user](https://docs.kernelci.org/api_pipeline/api/local-instance/#create-an-admin-user-account) in Mongo DB.
 The user can also generate an [API token](https://docs.kernelci.org/api_pipeline/api/local-instance/#create-an-admin-pipeline-token) to use API endpoints.
 
+For simple user management (invite, accept, login, whoami), use the helper
+script `scripts/usermanager.py`. It accepts an optional
+`usermanager.toml` config file (including multiple instances) or
+`KCI_API_URL` / `KCI_API_TOKEN` / `KCI_API_INSTANCE` environment variables.
+
 Ultimately, there will be a web frontend to provide a login form.  We don't
 have that yet as this new KernelCI API implementation is still in its early
 stages.

api/config.py

@@ -16,6 +16,8 @@ class AuthSettings(BaseSettings):
     algorithm: str = "HS256"
     # Set to None so tokens don't expire
     access_token_expire_seconds: float = 315360000
+    invite_token_expire_seconds: int = 60 * 60 * 24 * 7  # 7 days
+    public_base_url: str | None = None
 
 
 # pylint: disable=too-few-public-methods