[MB-0602][P2] Reduce code-scanning noise by separating style findings

[FarisZR]

Summary

Separate style/static-noise findings from security scanning so security dashboards stay actionable.

Scope

• Reconfigure Codacy/SARIF integration and workflow categorization.
• Keep style output in dedicated lint workflow/reporting channel.

Acceptance Criteria

• Security dashboard is not dominated by style warnings.
• Style findings remain accessible in a non-security workflow.

Test Requirements (Mandatory)

• Validate SARIF categories and resulting alert types after workflow changes.

Dependencies

• MB-0601

Definition of Done

• Security scan signal quality improved.
• Documentation updated for where style findings live.

References

• Plan: docs/plans/2026-02-21-refactor-long-term-modernization-backlog-plan.md
• Backlog ID: MB-0602