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/store/compose.ts

@@ -3,8 +3,8 @@ import { client, setErrorMessage } from "@/jmap/client";
 import type { Email, EmailAddress, EmailBodyPart, Id, Identity, SetResponse } from "@/jmap/types";
 import { formatFullDate, uid } from "@/lib/format";
 import { formatAddress, parseMailto, sameAddress, uniqueAddresses } from "@/lib/address";
-import { escapeHtml, htmlToText, quoteText, replySubject, textToHtml } from "@/lib/text";
-import { sanitizeEmailHtml, sanitizeEditorHtml } from "@/lib/html";
+import { escapeHtml, htmlToText, quoteText, replySubject, textToHtml } from "@/lib/text/text";
+import { sanitizeEmailHtml, sanitizeEditorHtml } from "@/lib/text/html";
 import { toast } from "@/ui/toast";
 import { useMail, FULL_PROPS, BODY_PROPS } from "./mail";
 import { ensureScheduledMailbox, useScheduled } from "./scheduled";
@@ -12,7 +12,7 @@ import { formatScheduleTime, holdUntil } from "@/lib/schedule";
 import { t as translate } from "@/lib/i18n";
 import { BASE_PATH } from "@/lib/basePath";
 import { settings } from "./settings";
-import { emlFilename } from "@/lib/emlName";
+import { emlFilename } from "@/lib/text/emlName";
 import { fillPlaceholders, type PlaceholderContext } from "@/lib/templatePlaceholders";
 import { shareBody, type SharedContent } from "@/lib/shareTarget";