Enhance task logging

_As a funcX site administrator I want to access a report log so I can tell who used what compute resources_

## Assumptions
1. Capture all of the task lifecycle
2. Interchange batches changes back to the forwarder
3. New WebService endpoint to update task log
4. Forwarder hits this endpoint at lifecycle points

Capture when a task is finished

We need to refactor task logging to capture the new task states that are reported.

### Approach

- Use a new table for task events, rather than the existing tasks table
- Add logging actions when status reports are received
- Ensure we log the success and failure of a task
- Log exceptions raised by functions
- Include flexibility to store runtime if present in the result

Trace the WebService task-log update endpoint and the forwarder status-report path, then review how the existing tasks table records lifecycle state. Done means task events cover the lifecycle, success and failure, and function exceptions, with runtime stored when supplied and batches exchanged back to the forwarder.

Written by the indexing model from the issue text.