Assorted IMAP client robustness fixes

CHANGELOG

@@ -1,3 +1,21 @@
+unreleased
+  - added IMAP UIDPLUS support (RFC 4315): appendFullUID, copyUID, copyUIDs,
+    copyUIDR, uidExpunge, uidExpungeR, plus the APPENDUID/COPYUID/UIDNOTSTICKY
+    response codes and AppendUID/CopyUID types
+  - IMAP response parser is now case-insensitive for protocol keywords,
+    status codes and flag names (per RFC 3501); also surfaces untagged BYE as
+    a fatal response, accepts an empty SEARCH reply and a NIL LIST hierarchy
+    separator, and no longer lets atoms run past CRLF
+  - IMAP SEARCH string arguments are now quoted, LARGER/SMALLER no longer wrap
+    their size in braces, and SEARCH automatically adds CHARSET UTF-8 (and
+    sends the command UTF-8 encoded) when a query contains non-ASCII text
+  - assorted IMAP robustness fixes: accept a PREAUTH (and case-insensitive)
+    connection greeting; loop over SASL '+' challenge continuations (e.g.
+    XOAUTH2); handle non-synchronising {n+} and binary ~{n} literals in
+    getResponse; normalize a NIL message body to empty; read STORE result
+    flags from the FLAGS key and quote X-GM-LABELS; unify escapeLogin with
+    quoteIMAPString
+
 0.7 (2025-06-08)
   - updated to the lastest GHC, tested with 8.10.7 — 9.12.2 (PR #103)
     Thanks to @thomasjm