Phase 9: ESL superpowers — Chinese gloss + tone-rewrite

Inline Chinese gloss (offline) and a "say it more naturally" / tone-rewrite,
the two ESL features for the Mandarin-speaking writer.

Gloss: embedded English→Chinese dictionary (gloss.json.gz, 57k common words
built from ECDICT via scripts/build_gloss.py). lexicon gains Gloss()/Result.Gloss
and a lightweight GET /api/gloss/{word}; the right-click WordCard leads with the
中文; GlossTip shows it on a 350ms hover (reuses wordAt, so CJK is never glossed).
Offline + instant, works with the LLM down.

Rewrite: selecting text pops a SelectionBubble (✨更自然 + the tone vocabulary);
picking a style calls POST /api/docs/:id/rewrite (llm.RunRewrite, stateless,
owner-scoped) and shows a RewritePreview (original→rewrite, accept/cancel/retry).
Accept applies it in-editor.

Tests added in lexicon and suggestions. go build/vet/test, tsc, vite all clean;
live smoke vs a fake vLLM verified gloss + rewrite + 400/404/502 paths.

Claude-Session: https://claude.ai/code/session_016Yr6jELuRc7hyzYLccQKZd

BUILD_PLAN.md

@@ -81,16 +81,23 @@ Multi-session build. **Source of truth for what's done and what's next.** Update
 - [x] **Stop saving empty docs** — blank `Untitled` drafts now self-discard: `handleCreate` reuses an existing blank instead of stacking another; `openDoc` deletes the blank doc being left. Cleaned the 2 existing orphan empties from the live DB. (Backend also refuses to snapshot empties.)
 - Verified: go build/vet/test + tsc + vite all clean; live smoke on a throwaway binary — auto-snapshot on save, throttle holds at 1, manual snapshot, restore brings back exact text + leaves a `pre_restore`, empty doc → no snapshot, md/docx export with CJK+bold+heading+list, docx validates as "Microsoft Word 2007+".
 
+### Phase 9 — ESL superpowers ✅
+- [x] **Inline Chinese gloss (offline)** — embedded English→Chinese dictionary (`internal/lexicon/data/gloss.json.gz`, ~1.3MB, 57k common words built from ECDICT via `scripts/build_gloss.py`: frequency-gated to rank ≤50k, `[网络]`/slang/archaic sense-lines dropped, trimmed to ≤3 senses / 80 chars). `Lexicon` gains a `gloss` map + `Gloss(word)` (same `candidates()` de-inflection as defs/syns); `Result` gains a `Gloss` field. Two surfaces: the right-click **WordCard** now leads with the 中文 gloss, and a new lightweight `GET /api/gloss/{word}` (→ `{word, gloss}`, cached) backs the **hover tooltip**. Offline + instant, works with the LLM down (north-star reliability). Frontend: `GlossTip` (dark pointer-events-none bubble under the resting word; 350ms hover delay; reuses `wordAt` so CJK is never glossed — it's the source language), wired into `EditorCore`'s `onMouseMove`/`onMouseLeave` with a request-token guard, suppressed during selection/preview/other popovers.
+- [x] **"Say it more naturally" / tone-rewrite** — selecting text pops a `SelectionBubble` (✨更自然 + the tone vocabulary 学术/专业/轻松/幽默/创意/说服, mirrored from `ToneSelect`/`styleGuidance`). Picking a style calls `POST /api/docs/:id/rewrite` (`{text, style}` → `{rewrite}`), shown in a `RewritePreview` (original struck-through → rewrite, 用这个/取消, breathing-dot loading, gentle retry on failure). Accept applies it in-editor via `insertContentAt` over the captured PM range. Backend: `llm.RunRewrite` (one-shot Complete, `RewriteMaxRunes` 2000 cap, `cleanRewrite` strips stray wrapping quotes) + `rewriteSystemTemplate`/`styleGuidance` in `prompts.go`; handler in `internal/suggestions/rewrite.go` (owner-scoped 404, 400 on empty/too-long, 502 on LLM-down). **Stateless** — not persisted as a suggestion; the version history captures the resulting doc change.
+- Tests: `lexicon` gloss + Lookup-includes-gloss + inflection/miss; `suggestions` rewrite happy-path (style steering + de-quote asserted), empty→400, unknown-doc→404. go build/vet/test clean, tsc clean, vite build OK. Live smoke vs a fake vLLM (fresh port 8055, throwaway DB; pre-existing dev servers on :8077/:8099 untouched): gloss for `river`/inflected/CJK-empty/nonsense-empty, `word/happy` carries the gloss, rewrite returns text, empty→400, unknown→404, LLM-down→502; new CSS classes present in the built bundle.
+- **Known limitation**: `Gloss` tries the literal form first (matching defs/syns ordering), so an inflected word that is *itself* a separate ECDICT headword resolves to that entry rather than de-inflecting (e.g. `rivers` → the proper-noun "Rivers" sense, not `river`). The base form always glosses correctly; acceptable.
+
 ### Deferred (post-v1-local)
 - [ ] Authentik OIDC auth + session middleware  ← **on hold: user doing foundational work first**
 - [ ] Copyleaks Tier-2 + webhook HMAC
 - [ ] Dockerfile, docker-compose, Traefik, deploy to write.parodia.dev
 
 ### Next-up (post-v1 product, agreed with user 2026-06-26)
-- [ ] **Phase 9 — ESL superpowers**: inline Chinese gloss on hover/select; "say it more naturally" / tone-rewrite.
+- [x] **Phase 9 — ESL superpowers**: inline Chinese gloss on hover/select; "say it more naturally" / tone-rewrite. ✅ (see Phase 9 above)
 - [ ] **Phase 10 — organization & polish**: cross-doc search, folders/tags, tablet/touch polish, warm LLM-down failure states.
 
 ## Session log
+- 2026-06-26: **Phase 9 complete** (ESL superpowers: inline Chinese gloss + tone-rewrite). Decisions confirmed with user: gloss is an **offline EC dictionary** (instant, LLM-down-proof, fits the embedded-lexicon ethos), rewrite is a **selection bubble**. Data: `scripts/build_gloss.py` builds `internal/lexicon/data/gloss.json.gz` from ECDICT (66MB csv → 1.3MB gz, 57k freq-≤50k words, cleaned/trimmed). Backend: `lexicon` gloss map + `Gloss()`/`Result.Gloss` + `GET /api/gloss/{word}`; `llm.RunRewrite` + rewrite prompt/`styleGuidance`; `internal/suggestions/rewrite.go` (`POST /api/docs/:id/rewrite`, stateless, owner-scoped). Frontend: `GlossTip` hover tooltip (350ms delay, reuses `wordAt`, CJK-safe) + gloss line in `WordCard`; `SelectionBubble` + `RewritePreview` wired through `EditorCore` (onMouseMove/onSelectionUpdate, request-token guards, clears on edit/doc-switch); `api.glossWord`/`api.rewriteSelection`; CSS for the three new surfaces (+ print-hidden). Tests added in `lexicon` and `suggestions`. All builds/tests/vet/tsc/vite clean; live smoke vs fake vLLM on :8055 verified gloss + rewrite + 400/404/502 paths. Next: **Phase 10 (organization & polish).**
 - 2026-06-26: **Phase 8 complete** (Trust foundation: version history + export) + empty-doc fix. Backend: migration `0003_document_versions`; `internal/docs/versions.go` (throttled auto-snapshot wired into `update`, manual snapshot, restore-with-pre_restore, prune to 40 auto, owner-scoped via join) and `internal/docs/export.go` (pure-Go Tiptap-JSON → md/html/txt/docx, no deps, CJK-safe filenames via RFC 5987). `DocumentVersion` model + kind constants. Tests: `versions_test.go`, `export_test.go` (incl. valid-zip docx assertion). Frontend: `api.client` version/export methods; `ExportMenu` + `HistoryPanel` components wired into the title row; `@media print` stylesheet + `.petal-no-print` for the browser PDF path; `editorEpoch` remount on restore. Empty-doc fix in `App.tsx` (blank drafts reuse-on-create + discard-on-leave via refs to dodge stale closures); deleted 2 orphan empties from the live :8099 DB. Multi-session plan agreed: this session = Phase 8; **Phase 9 (ESL gloss + tone-rewrite)** next, then **Phase 10 (search/folders/polish)**; **auth/deploy (was Phase 11) shelved** until user's foundational work lands. All builds/tests/vet clean; live smoke verified the full version+export+restore flow end-to-end. Next: **Phase 9.**
 - 2026-06-25: Spec reviewed & amended (voice/grammar decoupled, ctx cap, routes, voice DB type, honey color, string-anchoring). Build plan created.
 - 2026-06-25: **Phase 0 complete.** Go module + chi server, config loader, React/Vite/Tailwind-v4 scaffold with full design tokens, frontend embedded & served by the binary, verified end-to-end. Toolchain: Go 1.24.4, Node 22, npm 10. Next: **Phase 1 (data layer)** — SQLite via modernc, models, seed `local` user.