Restructures the admin menu into a primary and secondary menu for better user experience.
The primary menu now shows the most common actions.
The secondary menu contains less frequent admin commands.
Refactors the Vikunja module to be triggered by a menu button instead of a command.
Adds "edit task" functionality to the Vikunja module.
Fixes a bug where the button dispatcher was calling a non-existent function.
This commit introduces a `ConversationHandler` for the `/vik` command, replacing the previous simple command.
The new implementation provides an interactive menu for users with admin permissions to:
- View their tasks from a hardcoded project (ID 1).
- Add new tasks to the same project.
The changes include:
- A new `ConversationHandler` in `app/modules/vikunja.py` to manage the interactive flow.
- Integration of the new handler in `app/main.py`.
- Removal of the old `/vik` command handler.
- A fix in `test_vikunja.py` to correctly load environment variables.
