Expose provenance-aware cross-project comparison candidates without automatic winner selection #32

User-authorized cross-project intent improvement, 2026-10-27. Coordination: PLF-20321. Execute through Heyasa / Willman only after native admission.

Existing evidence: core/decision.py currently uses overlap thresholds 60/20/5 percent. This is useful reuse advice, not a validated maturity or best-implementation ranking.
Observed source HEAD: e3fec7f8b196fc506bd3ffa8cd91e8a84ab2fb98.

Prerequisites: No implementation predecessor.
Before editing, read back prerequisite delivery and exact source contracts. An open proposal, accepted campaign or unmerged change does not satisfy a prerequisite. If unresolved, record one dependency and wait; do not allocate a competing implementation.

Acceptance criteria:

• Reuse compare_projects, Intract matching and existing semantic profiles; add stable source-bound candidate projection suitable for the Search/todo2code composition.
• Distinguish generated/deployment copies, exact clones, structural similarity and declared intent matches. Carry evidence and coverage; mark unsupported semantics unknown.
• Keep MERGE_PROJECTS/EXTRACT_SHARED_LIB recommendations advisory. LOC overlap thresholds cannot establish superior quality, compatible authority, license, effects or replacement safety.
• Regression fixtures cover identical, renamed, unrelated, generated-copy and missing optional dependency cases; no Planfile writes from the comparison operation.

Proposed scope (controller must admit exact scope):
src/redup/core/comparator.py, src/redup/core/decision.py, src/redup/reporters/comparison_reporter.py, tests/test_compare.py, tests/test_intent_integration.py

Execution contract: Autoryzacja użytkownika 2026-10-27: przeanalizować projekty ~/github//, zachować SSOT, stworzyć plan i tickety oraz zlecić wykonanie Heyasa. Jeden właściciel zapisu na ticket/worktree; lokalne testy i przygotowanie PR są dozwolone, merge tylko przez niezależny Validator. Nie jesteś sam w repozytorium: zachowaj cudze zmiany i aktywne tickety. Najpierw odczytaj bieżące HEAD, intencję, checkpoint, lease i PR; wznowienie właściwego zadania ma pierwszeństwo. Przed kodowaniem rozwiąż zależności i sprawdź przydatność już istniejącej implementacji; no-change wymaga dowodu. Nie twórz nowego repozytorium.

Delivery evidence: preserve original accepted intent and intentional differences; record tests and exact before/after revisions, native ticket, worktree, fencing, PR and Validator receipt. Rollback uses the existing protected project mechanism. Completion of this proposal requires verified acceptance, not merely a linked runtime ticket. If already implemented, document exact matching evidence and no-change.

Canonical work proposal: PLF-20326; execution receipts must link this ID. This issue is the GitHub projection of that proposal.

Strategy Metadata:

• planfile_id: PLF-20326
• repository: semcod/redup
• deduplication_key: cross-project-intent-improvement:2026-10-27:RED
• coordination: PLF-20321