feat(jira): per-user auth, lifecycle hooks, admin config endpoints

- Add jira_api_token field to User model + migration b042
- Per-user Jira client: user's corporate email + personal Atlassian token
- Admin-configurable Jira URL/project via system_configs (GET/PATCH /system/jira-config + POST /system/jira-test)
- Auto-create Jira ticket when a test is created (non-fatal)
- Push lifecycle comments on every state transition: draft→red_executing→blue_evaluating→in_review→validated/rejected→draft
- Rich ticket descriptions with technique, MITRE ID, priority from severity, labels
- UserOut.jira_token_set (bool) instead of exposing raw token
- PATCH /users/me/preferences now accepts jira_api_token

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/schemas/user.py

@@ -122,10 +122,13 @@ class PasswordChange(BaseModel):
 
 
 class UserPreferencesUpdate(BaseModel):
-    """Payload for updating current user's notification preferences and Jira account."""
+    """Payload for updating current user's notification preferences and Jira settings."""
 
     notification_preferences: dict | None = None
     jira_account_id: str | None = None
+    # Personal Jira API token (Atlassian token) — write-only, stored encrypted at rest.
+    # Set to empty string "" to clear the token.
+    jira_api_token: str | None = None
 
 
 class UserOut(BaseModel):
@@ -141,5 +144,15 @@ class UserOut(BaseModel):
     last_login: datetime | None = None
     notification_preferences: dict | None = None
     jira_account_id: str | None = None
+    # Never return the raw token — just indicate whether it is configured.
+    jira_token_set: bool = False
 
     model_config = ConfigDict(from_attributes=True)
+
+    @classmethod
+    def model_validate(cls, obj, *args, **kwargs):  # type: ignore[override]
+        instance = super().model_validate(obj, *args, **kwargs)
+        # Derive jira_token_set from the ORM object without exposing the value
+        if hasattr(obj, "jira_api_token"):
+            instance.jira_token_set = bool(obj.jira_api_token)
+        return instance