Story 1.8: Configure Stryker Mutation Testing (Growth)

As a quality engineer, I want Stryker mutation testing to run on a scheduled basis, So that we measure real test effectiveness and identify gaps in our test suites.

FRs: FR58 | Sprint: Growth

Acceptance Criteria:

• Stryker configured for backend Jest test suites with incremental mode
• Stryker configured for OPEA pytest suites (stryker-python or equivalent)
• Mutation testing runs weekly via scheduled pipeline (not on every MR)
• Mutation score reported per component; components below 80% generate a task
• Dashboard or report accessible for trend tracking
• Configuration documented in CONTRIBUTING.md or equivalent

NFRs: NFR1, NFR6, NFR11