[comp log_backend] Component Assumptions of Use creation

## What

Create the Component Assumptions of Use (`wp__requirements_comp_aou`) for the component log_backend. These are SW safety requirements for users of the component, to be integrated in their requirements management system.

## How

**Process step:** [wf__req_comp_aou](https://eclipse-score.github.io/process_description/main/process_areas/requirements_engineering/requirements_workflow.html#wf__req_comp_aou)

## Definition of Done

All criteria of the [Requirements Inspection Checklist](https://eclipse-score.github.io/process_description/main/process_areas/requirements_engineering/guidance/requirements_inspection_checklist.html) are met.

## Template & Folder Structure

- **Template:** [AoU Component Requirements Template](https://eclipse-score.github.io/module_template/main/score/component_example/docs/safety_analysis/aou_requirements.html)
- **Folder:** `score//docs/safety_analysis/` – see [Module Folder Structure](https://eclipse-score.github.io/module_template/main/index.html#module-layout)

*Please apply the linked template and folder structure to ensure consistency across the S-CORE project.*

Read the linked wf__req_comp_aou process, the Requirements Inspection Checklist, and the AoU Component Requirements Template first. Create the log_backend artifact under score/log_backend/docs/safety_analysis/ using the prescribed module folder structure. Done means all checklist criteria are satisfied and the safety requirements are ready for integration into users' requirements management systems.

Written by the indexing model from the issue text.