launch ParseSemver discards strconv.Atoi range error so an over-int64 version component clamps to MaxInt64 and can wrap negative in DeriveNext

launch ParseSemver discards strconv.Atoi range error so an over-int64 version component clamps to MaxInt64 and can wrap negative in DeriveNext

Evidence

internal/core/launch/semver.go:43-45 — major, _ := strconv.Atoi(m[1]) (×3) discards ErrRange; the regex admits an unbounded digit run (0|[1-9]\d*). A tag v99999999999999999999.0.0 parses to Major=MaxInt64 silently. ComputeRetention then refuses a cut naming a non-existent tag; two over-int64 tags collapse to one lossy Semver. spec/spec.go:115-130 handles this exact case explicitly — this is the un-swept sibling the principles-doc meta-rule predicts.

Adversarial verdict: CONFIRMED (substantive-low)

Atoi clamp reproduced. Reachable via abcd launch --dry-run → ComputeRetention, and via changelog.DeriveNext where next.Major++ on a breaking bump wraps MaxInt64→MinInt64, producing v-9223372036854775808.0.0 — the wrap the spec.go fix warns of. Input is the repo's own git tags (self-inflicted, not attacker), hence low. Fix: mirror spec.go — return an error on ErrRange; GitExistingTags already drops erroring tags, so behaviour is preserved for all valid tags.