R6: mark phase done in PRERELEASE.md + log refinements

PRERELEASE.md

@@ -22,7 +22,7 @@ the edge before prod. Each phase maps back to the owner's raw pre-release TODO l
 | R3 | Edge hardening | 2 + 8 + 3 | **done** |
 | R4 | Push enrichment + kill the last poll | 4 + 5 | **done** |
 | R5 | Bundle slimming | 6 | **done** |
-| R6 | Refactor + docs reconciliation + de-staging | 7 | todo |
+| R6 | Refactor + docs reconciliation + de-staging | 7 | **done** |
 | R7 | Final stress run + tuning | 9b | todo |
 | → | Stage 18 — prod contour deploy | — | see [`PLAN.md`](PLAN.md) |
 
@@ -156,7 +156,7 @@ landing (≈24 KB) is reported separately and kept minimal. Same CLI + exit-code
 step is unchanged.
 - Critical files: `ui/scripts/bundle-size.mjs`; no app code changed.
 
-### R6 — Refactor + docs reconciliation + de-staging *(TODO 7)* — near last
+### R6 — Refactor + docs reconciliation + de-staging *(TODO 7)* — done
 Behaviour-preserving only. Three separable, separately-committed passes: (a) mechanical
 **de-staging** — remove `Stage N`/`TODO-N` references from code, comments and service
 READMEs (rename `stage6_test.go`); (b) **docs↔code reconciliation** — reconcile
@@ -348,3 +348,35 @@ Then Stage 18.
     app total (≈97) and landing total (≈24.5). Same CLI + exit-code contract, so the CI step is unchanged.
   - **No app/source/build change** (`App.svelte`, `lib/i18n/`, `vite.config.ts` untouched); no schema
     change, no contour wipe. The stale "~82 KB" figure was corrected in `bundle-size.mjs` and `ui/README.md`.
+
+- **R6** (interview + implementation):
+  - **Locked decisions:** apply **both** wire/code structural changes (**B** + **A**) and **only C1+C2** of
+    the test consolidation (not C3/C5); strip the `*(Stage N)*` tags from **all current-state docs**
+    (ARCHITECTURE / FUNCTIONAL+`_ru` / TESTING / UI_DESIGN), keeping PLAN.md / PRERELEASE.md / CLAUDE.md as
+    history; **split `stage6_test.go`** by domain. The `h2cMaxConcurrentStreams` sizing stays an **R7**
+    concern (tuning, not behaviour-preserving); the R2 early run forced no code fix, so nothing was carried in.
+  - **(a) De-staging:** removed the `Stage N` / `TODO-N` / `(RN)` references across code, comments, service
+    READMEs and the current-state docs, rewording narratives to present tense (no technical content lost).
+    Renamed the only stage-named identifiers (`registerStage8`→`registerSocialOps`,
+    `registerStage11`→`registerLinkOps`) and split `stage6_test.go` (`TestEmailLoginFlow`→`email_test.go`;
+    `TestGuestAutoMatchLeavesNoStats`+`provisionGuest`→`account_test.go`). De-staged the `.fbs`/`.proto`
+    comments and regenerated: only the `.proto`-derived Go docstrings (`*_grpc.pb.go`, `push.pb.go`) changed —
+    flatc strips schema comments, so the FB Go/TS bindings were untouched.
+  - **(b) Reconciliation:** the docs were accurate (each R-phase baked its own); the one drift was a stale
+    "guest-reaping deferred (TODO-3)" note in `ARCHITECTURE.md` §3 — guest reaping is implemented, so the
+    note was replaced with the current behaviour (FUNCTIONAL/TESTING already described it).
+  - **(c) B — dead `opponent_moved` scalars:** removed `seat/action/score/total` from `OpponentMovedEvent`
+    (`pkg/fbs/scrabble.fbs` + the `notify` emit + the round-trip test); regenerated FB Go + TS. No reader
+    used them (the UI codec/mock take `move`/`game`/`bag_len`; the gateway forwards the payload verbatim).
+    A pre-release wire-slot renumber — free with no prod data, no DB change.
+  - **(c) A — shared FB builders:** new `scrabble/pkg/wire` holds the single definition of the nested wire
+    tables (GameView / MoveRecord / StateView / AccountRef / Invitation) shared by the backend `notify`
+    encoder and the gateway `transcode`; both map their own source types to neutral `wire.*` structs and
+    delegate. **Honest tradeoff:** the verbose `Start/Add/End` + reverse-prepend boilerplate is now written
+    once, but the field *set* is still mapped per side, and the new package makes the change net **+~145 LOC**
+    — a single-source / anti-drift win for the fiddly mechanics rather than a line-count cut. Behaviour-
+    preserving: the two sides' field sets were verified identical and the round-trip tests pass unchanged.
+  - **(c) C1+C2 — inttest fixtures:** moved the cross-file service/game fixtures (`newGameService` was used by
+    10 files) into `backend/internal/inttest/helpers.go`; single-file helpers stay local. Pure relocation.
+  - **No schema change → no contour DB wipe.** Regression gate: the full unit + integration + UI suites plus
+    the R7 stress run.