TrustBeacon 0.1.11 - implemented scoring model

The score summarizes evaluated public observations. It is not a probability of delivery, a security certification, or an Operations Research priority ranking.

Each scored finding has a maximum of 10 points. PASS receives 10; WARN receives 6-9 under the existing normalizer; FAIL receives 0. INFO is excluded from both earned points and the denominator. Total is round(earned / possible * 100). When no findings are scored, the legacy calculator returns 0; inspect findings rather than interpreting this as a measured failure rate.

DKIM changes
- Automatic discovery is INFO, even if keys are found. The active sender is unknown.
- Per-selector evidence is always INFO and adds no scored points.
- For explicitly supplied selectors, at most one summary is scored.
- All supplied keys passing the supported DNS/key checks: PASS for that limited public-key assessment only.
- Missing, malformed, revoked, weak or test-mode supplied keys: WARN, unless an unknown lookup/unsupported check leaves the assessment incomplete (INFO).
- Unknown/unsupported results: INFO. Actual outgoing authentication always remains not_tested.

Scoring thresholds and the other checkers are unchanged from 0.1.10. An unknown check being excluded can leave a high overall score; exclusion must never be described as a pass. Extra DKIM selectors can no longer inflate the overall grade.

Grades: >=95 A+, >=90 A, >=85 B+, >=80 B, >=75 C+, >=70 C, otherwise Needs Attention.

Category labels average non-INFO findings in the existing group mapping. >=90 Excellent, >=75 Good, >=60 Fair, otherwise Needs Attention. A group with no scored findings shows Additional Review Recommended.
