some more fixes

simplify/guidelines/errors-and-feedback.md

@@ -0,0 +1,37 @@
+# Errors and feedback
+
+## Quiet errors, loud logs
+
+The bar is Mailspring. The user runs it against the same Google account and has never seen a sync
+error in it. What Mailspring actually does: retries connection errors at the call site, shows nothing
+for a single failure of any kind, raises a visible error only after five exits in five minutes, and
+logs every caught exception to a per-account file.
+
+So: a transient failure is the status chip's business and the next poll's, never a toast. Toast only
+what a person can act on, which is a short list: paused, signed out, a missing permission, a write
+that was dropped for good.
+
+Every failure goes to the app's log file in the app data directory, `margin-mail.log` and its
+equivalents. Engine passes, message bodies, IPC errors through the `call` wrapper, uncaught webview
+errors. When the user reports an error, read that file before theorising.
+
+An app that toasts on the first failure and logs nothing to disk gives the user noise and gives you
+nothing to debug with. That is what this replaced.
+
+## No silent waits
+
+Any action that waits on the network or a slow operation changes something on screen at once. A
+control that looks identical before and after being pressed reads as broken, and a second press
+fires the call twice.
+
+The pattern, per the apps' own `docs/conventions.md`: a string phase union on the handler
+(`"idle" | "fetching" | "error"`), `data-phase` or `data-busy` on the control, `disabled` while in
+flight, a present-tense label ("Loading images...", "Sending"), and an outcome either way. Primitives
+carry the busy styling themselves, so the Banner action takes `busy` and `busyLabel` and Confirm
+relabels while busy.
+
+Never leave a `.catch(() => {})` on a user-pressed action. Never ship a button whose command nothing
+registers: a dead control is the limit case of the same complaint.
+
+The user's words, after clicking "Show images" and watching nothing happen for several seconds:
+"giving this feeling of stuck is extremely bad ux".