qp-regress

# qp-regress — Regression (re-run unchanged → surface_reach → delta) Input: a baseline `qp/run/<ts>/` and the same `qp/plan/tcs.tsv`. Output: `qp/regress/<ts>/`. ## 1. Re-run unchanged Execute the baseline's TCs with `qp-run` **without editing them**. Editing a TC to make it pass is a new run, not a regression — say so if the user asks for it. ## 2. surface_reach — did the batch leave the entry screen? ``` bash plugins/fh-qp/scripts/qp_tools.sh surface-reach qp/run/<new-ts>/evidence.tsv ``` | result | meaning | |---|---| | `REACHED n/n` | every TC observed a screen other than the modal (entry) one | | `PARTIAL k/n` | some did — report **which** did not, by tc_id | | `NOT_REACHED 0/n` | the whole batch sat on one screen (a login wall, a dead env). Every FAIL in that run is **unmeasured**, not a detection — write that sentence in the report | | `UNMEASURED` (rc 10) | no evidence file / empty — not a zero | Denominator is **all TCs**, including ones that never executed; write `surface_reach.txt` with the raw line. ## 3. Per-TC delta — `delta.tsv` ``` tc_id baseline_status new_status changed note ``` One row per TC. `changed=yes` on any status change **or** on a same-status verdict whose `closure` moved from MACHINE to JUDGMENT (the check got weaker). A run where every row is `changed=no` may say "no regression"; a run reported only as "12 PASS both times" may not — the aggregate hides a swap. ## 4. Report — `report.md` First 8 lines: target · engine/adapter/evidence · `#mtm...