Record what the live 0.15.5 run actually verified

The REST credential path is no longer untested: password change, app passwords
and enabling and disabling 2FA were all exercised against the live server on a
real mailbox. The registry path is still mock-only.

Also correct the locale line. Both methods it can use are 0.16 ones, so on an
older server neither is reachable and the browser locale still wins — the fix
helps 0.16+ users, and the entry should not imply otherwise.

README.md

@@ -53,7 +53,7 @@ ihasmail is a JMAP-first web client: mail, calendars, contacts, files, filters a
 
 **Settings**
 - **Dates & times**: language/region (every one of the ~620 locales CLDR has data for, each named in its own language and script), date order (locale default, `22.11.2025`, `22/11/2025`, `11/22/2025` or ISO `2025-11-22`) and 12h/24h clock, applied everywhere — message list and headers, calendar, contacts, files, sessions. The default comes from the locale configured for the account in Stalwart (`x:Account/get`), falling back to the browser's; POSIX forms are normalised (`de_DE.UTF-8` → `de-DE`) and script modifiers preserved (`sr_RS@latin` → `sr-Latn-RS`). Numerals follow the locale (`٢٢.١١.٢٠٢٥` for `ar-EG`), except under ISO 8601, which pins date *and* clock to Latin digits. Dates are **entered** through custom pickers in the same format (browsers render `<input type="date">` in their own locale and ignore the page's), with a calendar popover, a time list, keyboard navigation, and lenient typing — `22.11.`, `221125`, `6:23pm` and bare ISO all parse
-- **Self-service credentials** in Settings › Security: change your password, manage **app passwords** (a separate password per mail app or device, revocable on its own), and turn **two-factor authentication** on or off by scanning a QR code. Enrolment codes are verified before anything is stored, so a mistyped key cannot lock you out, and switching 2FA on moves this browser's session onto a dedicated app password instead of signing you straight back out. Works against both Stalwart generations: the `x:AccountPassword` / `x:AppPassword` registry objects on 0.16+, and the `/api/account/auth` REST endpoint on 0.15.x
+- **Self-service credentials** in Settings › Security: change your password, manage **app passwords** (a separate password per mail app or device, revocable on its own), and turn **two-factor authentication** on or off by scanning a QR code. Enrolment codes are verified before anything is stored, so a mistyped key cannot lock you out, and switching 2FA on moves this browser's session onto a dedicated app password instead of signing you straight back out. Works against both Stalwart generations: the `x:AccountPassword` / `x:AppPassword` registry objects on 0.16+, and the `/api/account/auth` REST endpoint on 0.15.x (the latter confirmed live)
 - Identities & signatures, **Sieve filters** (visual rule builder that round-trips to a Sieve script, plus a raw script editor with server-side validation), out-of-office (`VacationResponse`), folders, labels, templates, notifications, calendar defaults, sessions (sign out other devices), keyboard shortcuts, import/export of settings
 
 **Platform**
@@ -133,10 +133,10 @@ Verified against the mock server and, for the core mail flows, against a live St
 
 - **HTML signatures** — Stalwart caps identity signatures at 2 KB. ihasmail compacts pasted HTML, moves images to Files and, if still too large, keeps the full signature in Files behind a short marker (other clients see a text fallback). The end-to-end flow (save → compose → send with inline logo) is implemented but not yet confirmed on the live server.
 - **Files** — the live server runs an older Stalwart build than `main`; `FileNode/query` there rejects `isTopLevel`/`parentId` filters, so ihasmail falls back to listing all nodes and building the tree client-side. Upload/rename/move/delete still need a live pass.
-- **Self-service credentials** — verified end to end against the mock (which enforces the same rules: current password required, password policy, a TOTP code on every request once 2FA is on, app passwords exempt from it). The **0.16 registry path is not yet confirmed against a real 0.16 server**, and the **0.15.x REST path is not confirmed at all**; the live server is 0.15.5. Password changes are also refused by Stalwart for accounts backed by an external directory (LDAP/SQL/OIDC) — the server's own message is shown when that happens.
+- **Self-service credentials** — the **0.15.x REST path is confirmed live** against Stalwart 0.15.5 (2026-08-24): password change, app passwords, and enabling and disabling 2FA, on a real mailbox. The **0.16 registry path has only been exercised against the mock**, which enforces the same rules a real server does (current password required, password policy, a TOTP code on every request once 2FA is on, app passwords exempt from it) — it still wants a pass against a real 0.16 server. Password changes are refused by Stalwart for accounts backed by an external directory (LDAP/SQL/OIDC); the server's own message is shown when that happens.
 - Recurring events: colour/category/edit/delete apply to the whole series (per-occurrence overrides aren't supported by the server yet).
 - Editable date boxes are always Gregorian and in Latin digits, even for locales whose *display* uses another calendar or numbering system (`fa-IR`, `th-TH`, `ar-EG`) — they keep the locale's field order and separator, but a Buddhist-era year in a text box does not round-trip against the Gregorian calendar grid. Non-Gregorian calendar support is not implemented.
-- The account locale is read with Stalwart's `x:Account/get`, which needs the `sysAccountGet` permission; where a regular user is not granted it, ihasmail silently falls back to the browser locale and the setting can be chosen by hand.
+- The account locale is read from `x:AccountSettings/get`, whose permission the built-in user role has, falling back to `x:Account/get` (which needs the admin-only `sysAccountGet`). Both are Stalwart 0.16 methods: **on older servers neither is reachable** — they do not implement the registry and reject a request that so much as names the `urn:stalwart:jmap` capability — so there the locale still falls back to the browser's and can be chosen by hand.
 
 ## Roadmap / not yet