Session 0018.0 (Wave 9): rewrite legacy session refs in transcript bodies + README scoping

- Rewrite every legacy `Session L` / `Session M.1` etc. reference inside
  transcript bodies to the numeric form (`Session 0012.0` / `Session 0013.1`),
  via a mechanical Python sed pass scoped to canonical-filename transcripts
  only (502 replacements across 39 files; 21 files in this published repo +
  18 sibling files in `~/git/ohm-infra/`). The §23 rename was originally
  filename-only — session 0018.0 reverses that and rewrites the bodies too,
  so cross-references inside a transcript match the filename you'd browse
  to. The mapping table (`A → 0001` … `N → 0014`) lives in
  `SESSION-PROTOCOL.md` §1 (also amended this session) for anyone hitting
  an old external link.

- Amend README.md:
  - New "Where the record begins" section noting OHM started with two
    vibe-coded prototypes (no transcripts; the discipline that produced this
    record didn't exist yet). The transcripts here begin at the
    spec-driven-development phase — not at the literal beginning of OHM.
  - Update the existing "Sessions 0001 through 0013 originally shipped
    under a letter-form naming" paragraph to reflect that body refs are
    now also in numeric form.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

0014/SESSION-0014.0-TRANSCRIPT-2026-05-28T07-01--2026-05-28T08-25.md

@@ -491,7 +491,7 @@ sections accumulate these over time.)
 ```
 You are the OHM roadmap driver, Session 0015.0 (= the session that
 would have been labeled "Session O" under the legacy letter form).
-Session 0014.0 (Session N) executed a heavy Wave 7 + the #23
+Session 0014.0 (Session 0014.0) executed a heavy Wave 7 + the #23
 transcript rename — read this whole prompt before doing anything.
 
 # What Session 0014.0 shipped
@@ -516,8 +516,8 @@ show` or the deploy log):
    overlay keys to `npm run build`'s process.env so they reach
    Vite's `loadEnv()`. Pre-1.1.0 deploys shipped bundles with empty
    VITE_*, which silently disabled **Cloudflare Turnstile since
-   rfc-app v0.12.0** (Session K) and **Amplitude analytics +
-   session replay since rfc-app v0.15.0** (Session L). Both were
+   rfc-app v0.12.0** (Session 0011.0) and **Amplitude analytics +
+   session replay since rfc-app v0.15.0** (Session 0012.0). Both were
    confirmed broken by curl'ing the deployed bundle and grepping
    for the expected key strings (neither was present) — fixed via
    bundle re-grep (both now in the v0.18.0 bundle at
@@ -666,7 +666,7 @@ a. **flotilla: per-deployment "expected VITE_* keys" manifest +
    keys" candidate — these may be the same item.
 
 b. **flotilla: SSE-keepalive SIGTERM holding past 60s SSH watchdog
-   timeout.** Session I noted it (§19.2); hit 3× more this session
+   timeout.** Session 0009.0 noted it (§19.2); hit 3× more this session
    (deploy rows 23, 24, 25 all aborted-but-healthy). The watchdog
    timeout doesn't reflect the actual restart success. A flotilla
    minor (v1.2.0?) that pre-drains SSE connections before
@@ -676,7 +676,7 @@ c. **rfc-app: framework should accept an `EMAIL_HELO_DOMAIN` env
    override** (or auto-derive from EMAIL_FROM's domain) and pass
    `local_hostname=` to `smtplib.SMTP()`. Without this, the
    IP-allowlist-only SMTP relay path isn't viable for any
-   deployment — only SMTP AUTH paths work. Path C in the Session N
+   deployment — only SMTP AUTH paths work. Path C in the Session 0014.0
    triage couldn't proceed without a framework change.
 
 d. **flotilla / framework: .env quote-stripping inconsistency.**

0014/SESSION-0014.1-TRANSCRIPT-2026-05-28T07-08--2026-05-28T07-40.md

@@ -1,6 +1,6 @@
-# Session N.1 — Transcript
+# Session 0014.1 — Transcript
 
-> Parent: SESSION-N-TRANSCRIPT-2026-05-28T07-01--<end>.md
+> Parent: SESSION-0014.0-TRANSCRIPT-2026-05-28T07-01--<end>.md
 > Date: 2026-05-28 (PST)
 > Start: 2026-05-28T07-08 PST
 > End:   2026-05-28T07-40 PST
@@ -346,6 +346,6 @@ lesson + §5 of the protocol.
   failures. Driver N may want to either rename the remotes or
   update the prompt template.
 - **Subsession transcript:** this file, at
-  `~/git/ohm-infra/SESSION-N.1-TRANSCRIPT-2026-05-28T07-08--2026-05-28T07-40.md`.
+  `~/git/ohm-infra/SESSION-0014.1-TRANSCRIPT-2026-05-28T07-08--2026-05-28T07-40.md`.
   Driver N publishes this via `publish-transcript.sh` alongside
   the parent session transcript.