v1.2.0

Additive only — no behavior changes for existing code (ROADMAP §4).

• Added NewSkip(skip, code, msg) and WrapSkip(skip, err, msg) —
  caller-skip constructors for error factories (external review round 6). A
  helper like apperr.NotFound(msg) built on plain New records its own
  line in every trace; skip=1 points the frame at the factory's caller
  instead (zap AddCallerSkip precedent). Separate functions, so the
  New/Wrap hot path is unchanged. skip=0 is exactly New/Wrap; a
  skip past the top of the stack records the "unknown" frame; a negative
  skip panics. Core coverage reaches 100% — the over-skip test exercises
  the previously unreachable caller() failure branch.