chore(agentic): speed-ups plan Steps 1, 4 (N2/R8/R9), 6

Static/tooling slice of docs/dev/notes/AGENTIC-SPEEDUPS-PLAN.md — no build or
runtime environment needed to verify any of it.

- Step 6 / N7: add a VERIFY: line to the investigation-brief template
  (docs/dev-process.md) and the CLAUDE.md dispatch-preflight checklist — the
  brief must now name the exact probe/verify invocation that proves the task
  done, or state that runtime verification is impossible here.
- Step 4 / N2: tools_pc/README.md — indexes the ~60 scripts with a
  living vs artifact marker so closed-finding artifacts can be archived.
- Step 4 / R8: tools_pc/gen_findings_index.py -> docs/dev/findings-index.csv
  (label, bucket, one_liner, status_raw) — grep-before-you-read aid for the
  ~200 KB finding log. Heuristic parser of the §F/§H tables.
- Step 4 / R9: tools_pc/gen_env_probes.py — re-greps live getenv("GE_*")
  sites and reports NEW/GONE drift vs docs/dev/GE-ENV-PROBES.md (keeps the
  curated prose, only checks the site map). Doc reconciled: 7 new probes
  added, GE_D54 kept as a tombstone.
- CI: validate job now runs both generators with --check.

Step 1 / N1 (HANDOFF preflight) applied in the local-only docs/HANDOFF.md.
Step 2 (verify.sh) and the HANDOFF/HANDOFF-ARCHIVE trim are left for a
session with a build environment.

docs/dev-process.md

@@ -101,6 +101,7 @@ KNOWN-GOOD / RULED OUT: <list — do not re-investigate>.
 PRE-FLIGHT ATTACHED: <probe output, baseline capture, PD-port pointer>.
 BUDGET: <N build->run cycles / ~M min>. On expiry: revert probes, write up with confidence.
 CONSTRAINTS: no game-logic changes; ABI/layout/format only; #ifdef PORT; documented in the finding log.
+VERIFY: <the exact tools_pc/verify.sh (or probe) invocation that proves this done — or, if runtime verification is impossible in this environment, say so and name what a human must run>.
 REPORT: (a) root cause + file:line evidence  (b) fix diff, or why not
         (c) probes left in tree  (d) confidence.
         Append any generalisable quirk to docs/porting-notes.md.