test: delete tests of dead eval code (A)

- A1: the retired Eng lexical oracle (evaluateEngSeedCoverage,
  isEngSeedDecisionAUQ), the completion-handoff detector and the retained
  corpus had no paid caller since v1.87.6; delete their 26 replay files,
  ~2.6k helper LOC and fixtures, and the dead blocks in 8 mixed files
  (live hasNativePlanTerminal / batching assertions stay).
- A2: dead viewport approvers in autoplan-artifact-permission and their 11
  replay files + fixtures; recorder/launcher cases stay.
- A3: never-wired oracles and seeders (autoplan-phase-order,
  eng-finding-fixture, ceo-paired-fixture, design-ui-scope,
  plan-skill-completion, pty-current-screen, required-reads,
  transcript-section-logger); plan-seed-submission now decodes through the
  production createPtyScreen; section manifests name their actual guard.
- A4: zero-reference helper exports, plus execGit and invokeAndObserve
  found by the reachability pass.
- 52 fixtures orphaned by the deletions; touchfile and selection-table
  entries for every deleted path.

codex/sections/manifest.json

@@ -2,7 +2,7 @@
   "$schema": "https://gstack.dev/schemas/section-manifest.json",
   "skill": "codex",
   "version": 1,
-  "note": "PASSIVE registry (v2 plan T9 / CM2). Fields are IDs, file paths, human titles, and human-readable trigger text ONLY. The skeleton's Step 1 mode dispatch is the ONLY place that decides WHEN to read a section (the three modes are mutually exclusive — at most one section loads per invocation); required-reads live in the E2E fixtures. No machine predicate here — see docs/designs/v2_PLAN.md:663.",
+  "note": "PASSIVE registry (v2 plan T9 / CM2). Fields are IDs, file paths, human titles, and human-readable trigger text ONLY. The skeleton's Step 1 mode dispatch is the ONLY place that decides WHEN to read a section (the three modes are mutually exclusive — at most one section loads per invocation); required section reads are checked by test/carve-section-loading-codex.test.ts. No machine predicate here — see docs/designs/v2_PLAN.md:663.",
   "sections": [
     {
       "id": "review-mode",