[comp log_backend] Component Security Analysis creation

## What

Create the Component Security Analysis (`wp__sw_component_security_analysis`) for the component log_backend. This bottom-up security analysis verifies the component architecture and identifies mitigations linked to Component Requirements or Assumptions of Use.

## How

**Process step:** [wf__analyse_sec_comparch](https://eclipse-score.github.io/process_description/main/process_areas/security_analysis/security_analysis_workflow.html#wf__analyse_sec_comparch)

## Definition of Done

All criteria of the [Security Analysis Checklist](https://eclipse-score.github.io/process_description/main/process_areas/security_analysis/guidance/security_analysis_checklist.html) are met.

## Template & Folder Structure

- **Template:** [Component Docs – Security Analysis](https://eclipse-score.github.io/module_template/main/score/component_example/docs/index.html)
- **Folder:** `score//docs/security_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.*

Start with the linked wf__analyse_sec_comparch process step and Security Analysis Checklist, then review the Component Docs – Security Analysis template and Module Folder Structure. Create the analysis under score//docs/security_analysis/ for log_backend and verify that every checklist criterion is met.

Written by the indexing model from the issue text.