docs: record the userscript retry queue

CLAUDE.md

@@ -78,11 +78,24 @@ Bromite userscript (isolated world, per-site adapters, localStorage cache)
 1. **Site adapters** — one per host, `detect(location, document)` returns page `type` + IDs. Identify type/IDs from **URL regex** (most stable); pull `title`/`cover` from **`og:title`/`og:image` meta tags**, not CSS classes.
 2. **API client** — `apiGet/apiPut/apiDelete` with bearer header; `localStorage` key `mangabm:cache` for instant render + offline fallback.
 3. **Progress logic** — auto-upsert `last_chapter` only when `chapterNum >= stored last_chapter_num` (re-reading old chapters must not regress progress; unparseable -> set current). Manual panel override forces any value.
-4. **UI** — rendered inside a **Shadow DOM** root to isolate from site CSS
+4. **Retry queue** — every write goes through `pushBookmark`/`pushDelete`, so a
+   failed mutation is parked in `localStorage` (`mangabm:queue`) and replayed on
+   the next navigation, reconnect, or `refresh()`. Entries are markers
+   (`{key, op, sendStatus, attempts}`), never payloads — the body is read from
+   the cache at send time, so one entry per key gives ordering and coalescing for
+   free. `sendStatus` is **sticky**: while an archive is pending, later writes to
+   that key keep carrying the bucket, which is what stops a successful
+   in-between write from silently un-archiving the series. `refresh()` drains
+   before it fetches and overlays anything still pending, so the list never
+   flaps. A 400 drops the entry, a 401 aborts the pass and keeps the queue, and
+   transient failures retry to a cap of 10. Latest-chapter writes deliberately
+   stay out of the queue. See
+   `docs/superpowers/specs/2026-07-27-offline-retry-queue-design.md`.
+5. **UI** — rendered inside a **Shadow DOM** root to isolate from site CSS
    (critical on mobile). Three tabs (All / Favourites / Archived) and a row of
    link chips to the web UI and both manga sites; `WEB_BASE` sits in the CONFIG
    block next to `API_BASE`.
-5. **SPA navigation** — Asura is Astro, client-routed on the comic/chapter pages: patch `history.pushState`/`replaceState` + listen `popstate`, re-run `detect()` on URL change so auto-update fires without reload. Demonic uses classic reloads (initial `document-idle` run suffices).
+6. **SPA navigation** — Asura is Astro, client-routed on the comic/chapter pages: patch `history.pushState`/`replaceState` + listen `popstate`, re-run `detect()` on URL change so auto-update fires without reload. Demonic uses classic reloads (initial `document-idle` run suffices).
 
 ### Live URL shapes (verified 2026-07-26, may drift — re-check against live pages before trusting)
 

userscript/manga-bookmark.user.js

@@ -1,7 +1,7 @@
 // ==UserScript==
 // @name         Manga Bookmark Sync
 // @namespace    mangabm
-// @version      1.3.0
+// @version      1.4.0
 // @description  Track read progress on Asura & Demonic and sync to a self-hosted backend. Bromite-compatible (no GM_* APIs).
 // @author       you
 // @match        https://asuracomic.net/*