Add alpha-hardening ADRs and issue plan from pre-release audit.

Lock alpha scope, tracker auth, TOPLOC fraud verification, and deferred multi-tracker money-path work; supersede legacy fraud issues with ADR-0018.

Co-authored-by: Cursor <cursoragent@cursor.com>

.scratch/alpha-hardening/issues/17-doc-duplicate-us020-dedup.md

@@ -0,0 +1,23 @@
+Status: ready-for-agent
+
+# 17 — DOC: Duplicate US-020 issue dedup
+
+## What to build
+
+Two files share the US-020 number with different slugs:
+
+- `docs/issues/20-memory-budget-shard-slots-and-dropout-relocation.md` (ready-for-agent)
+- `docs/issues/20-tracker-node-hardening.md` (done)
+
+Resolve numbering collision without losing history.
+
+## Acceptance criteria
+
+- [ ] Document canonical mapping in this issue's Comments or a short `docs/issues/README.md` note
+- [ ] Renumber or prefix disambiguation (e.g. keep done item as US-020a, renumber memory-budget to next slot) — **human approval before git mv**
+- [ ] Update any prd.json / cross-links that reference US-020 ambiguously
+- [ ] No production code changes
+
+## Blocked by
+
+Human approval for renumbering