Mission Run Overview
Mission Run: SymbolKey source_module provenance field
Give dead-symbol allowlist entries a stable machine identity so the refresh helper stops depending on fragile provenance-comment parsing.
The architectural dead-symbol gate relies on free-form provenance comments to know which module a still-dead allowlisted symbol came from. That makes a load-bearing safety property depend on comment hygiene and caps the #2853 refresh helper's coverage on same-name duplicates. This mission adds a stable, non-hashing machine identity (source_module) to SymbolKey, backfills it across the allowlist, and retires the comment-parsing path — without forfeiting the relocation-tolerance the content-tier keys were designed for.