fix: round 2 of the release review of 6.3.0

Round 2 (v6.2.0..0d044f6, BLOCK: 2 BLOCKER, 11 MAJOR, 1 MINOR), each fixed
behind a test that failed first.

- The git runner checks only words /bin/sh passes through unchanged (no
  quote, backslash, $, glob or brace) and refuses --output and its
  abbreviations: round 1's --output refusal was bypassed by quoting.
- fieldPaths: backticked paths are kept as written, parentheses and all; in
  plain text every path-like word counts, and a parenthesised note does not.
- plan-validator --steps-from reads the plan's ## Verification for an
  appended End-to-end step, and warns instead of failing under --soft.
- regression-check prints progress_status, the value progress.json takes;
  /trekexecute copies it.
- release-check: a plugin in a subdirectory is checked in its own directory,
  the suite is not run when a cheaper check already makes the answer exit 2,
  and a bad argument or a crash is exit 2.
- Skill routing looks a skill up among skills only, and builds the corpus
  vectors once.
- /trekexecute Phase 7.2 says plainly that remediation steps in the review
  template's own form stop with a re-plan; making them runnable is a later
  order (operator 2026-10-10).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

commands/trekexecute.md

@@ -1734,6 +1734,10 @@ log. It installs nothing.
 criteria runner's two screens (the allowlist of test runners, then the
 executor denylist), before the checkpoint:
 
+`steps.{N}.regression` is the JSON's `progress_status`, copied as it is: the
+CLI already speaks progress.json's words (`"blocked"` → `"unrunnable"`,
+`"error"` → `"not-run"`).
+
 | Exit | `steps.{N}.regression` | Executor |
 |------|------------------------|----------|
 | 0 | `"passed"`, or `"absent"` when the step has no `Regression:` (nothing new happens) | continue |
@@ -2205,7 +2209,13 @@ never typed by the operator, in this order (Cherny's):
 **A BLOCK is fixed by new plan steps, in a bounded loop.** The review writes
 every BLOCKER as a numbered `### Step R<n>` under `## Remediation Steps`
 (Handover 6: Files, Source finding, Test first, Verify, On failure). The fix is
-those steps, not improvised. Every stop below is stop class 4 (Phase 5.5):
+those steps, not improvised. **Today the loop runs only for steps written as
+runnable plan steps:** `Test first:` with its `File:` and `Verifies:`, and a
+`Verify:` that is one allowlisted test command. A step in the review
+template's own form (a prose `Test first:`, `Verify:` "re-run `/trekreview`")
+does not pass step 3, and the run stops with "re-plan from the review" — the
+usual outcome until a later order makes the template's steps runnable as
+written. Every stop below is stop class 4 (Phase 5.5):
 the run is `stopped`, and the merge stays closed.
 
 0. **On the wave path there is no loop.** The plan's sha256 binds the