issue-root-resolution

## Activation Contract Load when auditing a defect backlog for shared root causes, proposing a fix for an issue cluster, or closing issues as resolved/outdated. Complements `rdd-defect-workflow` (single-defect flow) — this skill governs the cluster-level method. ## Hard Rules - Read full bodies and comments, never titles. Classify against the actual code or PR diff, not descriptions of it. - Verify every "fixed" or "broken" claim against current `origin/main` the day you act. Compare report dates to fix merge dates: a repro filed before the fix landed is evidence about old builds, not current code. - Cluster defects by causal root, not surface. Each root gets a measured row in the meta-issue (#2471 style): issues attached, fix shape, state. - Before proposing any fix, produce a read-only mechanism map: one file:line anchor per claim, mechanism explained as implemented today. Report claim-vs-code mismatches explicitly; never force evidence to fit the hypothesis. Let the map shrink the proposal. - Rank solutions by what they DELETE: (1) removes a mechanism so the class becomes impossible, (2) static guard-ratchet making reintroduction a test failure, (3) localized predicate fix behind a failing repro test. New surface (verbs, flags, mechanisms) is last resort — defer until re-verified evidence demands it. - Extract maintainer choices as named D-items with recommended defaults. A maintainer condition recorded in an issue thread outranks any plan table, including yours. - Clos...