Group six more clusters out of web/src/lib

Takes the flat module count from 66 to 42, continuing what admin/ and
calendar/ started.

  lib/mailbox/  archiveDate, emptyFolder, folderMove, labelTree,
                mailboxName, mailboxRoute
  lib/sieve/    sieve, sieveApply, sieveFolders
  lib/input/    keyboard, swipe, touch, listSelection, dropUpload
  lib/notify/   notify, webpush, webpushEnable
  lib/sw/       swCache, swFacts, staleBuild
  lib/text/     html, markdown, text, emlName

FOUR THINGS THE FILENAMES GET WRONG, each checked by reading the file
rather than trusting what it is called:

  - appFolder is not a mailbox. It is the `ihasmail` folder in JMAP
    *Files*, where the client keeps signature images and synced settings.
    It stays flat.
  - format holds no formatting of text. It re-exports the date and clock
    formatters, so it belongs with dates/datetime, not with text/.
  - preview is the file viewer deciding what it can show without
    downloading, and source is where to point someone asking for this
    instance's AGPL source. Neither is about text.
  - notify is not Web Push. It is the tab title, the favicon badge and
    the new-mail sound -- in-app notification, which is why it sits with
    webpush rather than under sw/ with the service worker's own concerns.

threadScroll stays flat too: it decides where a conversation opens, which
is view state rather than a gesture, and input/ is honest only if
everything in it interprets something the reader did.

No behavior change. Almost every reference was on the @/ alias; eight
relative imports in files that did not move, or that moved away from a
sibling, needed rewriting by hand.

web/src/App.tsx

@@ -16,12 +16,12 @@ import { LoginPage } from "@/views/Login";
 import { AppShell } from "@/views/AppShell";
 import { MailView } from "@/views/mail/MailView";
 import { ComposerDock } from "@/views/compose/ComposerDock";
-import { setUnreadBadge } from "@/lib/notify";
-import { publishWorkerFacts } from "@/lib/swFacts";
+import { setUnreadBadge } from "@/lib/notify/notify";
+import { publishWorkerFacts } from "@/lib/sw/swFacts";
 import { PAINTED_FROM_CACHE, useSettings, syncedPart } from "@/store/settings";
 import { armSettingsSync, loadRemoteSettings, queueSettingsPush, settingsAlreadyLoadedFor, settingsSyncAvailable } from "@/lib/settingsSync";
 import { loadSettingsPolicy } from "@/lib/settingsPolicy";
-import { listenForVerification, renewWebPush } from "@/lib/webpushEnable";
+import { listenForVerification, renewWebPush } from "@/lib/notify/webpushEnable";
 import { plural, t, useLanguageVersion, whenLanguageReady } from "@/lib/i18n";
 import { confirmLeaveUnsaved, hasUnsavedChanges } from "@/lib/unsavedChanges";
 import { BASE_PATH, withBase } from "@/lib/basePath";
@@ -260,7 +260,7 @@ function AuthedApp() {
   });
   const appName = useSession((s) => s.session?.ihasmail?.appName) || DEFAULT_APP_NAME;
   useEffect(() => {
-    void import("@/lib/notify").then((m) => {
+    void import("@/lib/notify/notify").then((m) => {
       m.setBaseTitle(appName);
       setUnreadBadge(inboxUnread);
     });
@@ -284,7 +284,7 @@ function AuthedApp() {
   // Request notification permission lazily when enabled
   const notif = useSettings((s) => s.settings.desktopNotifications);
   useEffect(() => {
-    if (notif) void import("@/lib/notify").then((m) => m.requestNotificationPermission());
+    if (notif) void import("@/lib/notify/notify").then((m) => m.requestNotificationPermission());
   }, [notif]);
 
   // Nothing worth painting until the account's settings are in force; see the