Add adaptive weighted fitness scoring

[Pan14ek]

Purpose

Implement experiment/adaptive-weighted-fitness by adding a versioned adaptive scalar fitness score that combines structural and runtime evidence without changing existing fitnessScore or runtimeFitnessScore semantics.

Type

• 🧪 Experiment (fitness function research)
• ✨ Feature (new business logic)
• 🐛 Bug fix
• ♻️ Refactor / neutral change
• 📝 Documentation only

Changes

• Adds adaptiveFitnessScore, adaptiveFitnessScoreVersion, and adaptiveFitness as additive collector output fields.
• Adds ADAPTIVE_FITNESS_CONTEXT=auto|balanced|workload|slo|resource-pressure.
• Implements context-sensitive weighting over structural quality and runtime signals.
• Uses SLO/resource pressure classifications to penalize measured pressure even when baseline-relative deltas would hide it.
• Documents the adaptive scoring contract and marks experiment/adaptive-weighted-fitness as implemented.

Files changed

File	Change
fitness-metrics-collector/scripts/adaptiveScoring.ts	Adds adaptive weighted scoring, context selection, active weight metadata, and pressure-floor handling.
fitness-metrics-collector/scripts/collectMetrics.ts	Emits adaptive fitness fields alongside existing structural/runtime scores.
fitness-metrics-collector/scripts/collectMetrics.test.ts	Covers context profiles, auto selection, missing-signal renormalization, pressure penalties, and output writing.
backend/lined/docs/adaptive-weighted-fitness.md	Documents inputs, output contract, context selection, signals, and compatibility rules.
backend/lined/docs/README.md	Adds adaptive weighted fitness to the backend docs index.
backend/lined/docs/experiment-tasks.md	Marks experiment/adaptive-weighted-fitness as implemented.

Expected result

Metric	Baseline (main)	Branch	Direction
checkstyle_violations	unknown	unknown	neutral
spotbugs_total	unknown	unknown	neutral
line_coverage	unknown	unknown	neutral
critical_violations	unknown	unknown	neutral
code_smells	unknown	unknown	neutral
duplicated_lines_density	unknown	unknown	neutral
F score	unknown	unknown	neutral
SonarQube QG	unknown	unknown	neutral

Expected experiment impact: structural CI fitness remains unchanged in meaning. Runtime-aware scoring remains available as the fixed runtime scalar baseline, while adaptive scoring adds a context-sensitive scalar baseline for workload, SLO, and resource-pressure comparisons.

Checklist

• ./gradlew check passes locally
• ./gradlew jacocoTestReport passes locally
• No unintended changes to main business logic
• Branch name matches experiment/feature naming convention

Additional verification:

• npm test passes in fitness-metrics-collector (31/31)
• npm run build passes in fitness-metrics-collector
• git diff --check passes
• Critic review completed with no blocking findings

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud