feat(activesync): EAS 16.0 draft sync and calendar initial-sync in co…

[TDannhauer]

Pull request: Core EAS 16.0 driver and draft sync

Conventional commit message

feat(activesync): EAS 16.0 draft sync and calendar initial-sync in core driver

Report Drafts folder changes as CHANGE_TYPE_DRAFT, handle POOMMAIL2:Send and
draft Add/Modify via Mail/Draft, expose bound recurrence exceptions on initial
calendar sync at 16.0+, and unify calendar_import() return shape.

PR title

feat(activesync): EAS 16.0 draft sync and calendar initial-sync in core driver

Summary

• Draft folder sync (EAS 16.0+):
  • Export draft content changes as CHANGE_TYPE_DRAFT (not flag-only changes).
  • Handle inbound draft <Add> / <Modify> via Horde_Core_ActiveSync_Mail_Draft (append + replace-by-delete for edits).
  • Handle POOMMAIL2:Send on Drafts-folder Sync: build RFC822 via toRfc822Stream(), send via SMTP, delete source draft.
  • Set IsDraft on outbound mail messages from the Drafts collection at 16.0+.
• Calendar initial sync (EAS 16.0+):
  • Pass hide_exceptions => false to calendar_listUids() when protocol version ≥ 16.0 so bound recurrence exceptions appear as separate items on first sync (matches kronolith instance model).
• Connector:
  • calendar_import() always returns ['uid' => …, 'atchash' => …]; deprecated calendar_import16() delegates to it.
• Draft MIME bodies:
  • Horde_Core_ActiveSync_Mail_Draft parses Type-4 (MIME) bodies from iOS when POOMMAIL headers are omitted.
• Cleanup: clarify draft-send comment in Driver.php; fix typo.

Changed files

File	Change
lib/Horde/Core/ActiveSync/Driver.php	CHANGE_TYPE_DRAFT; draft send/edit path; hide_exceptions on initial calendar sync; IsDraft export
lib/Horde/Core/ActiveSync/Connector.php	Unified calendar_import(); deprecate calendar_import16()
lib/Horde/Core/ActiveSync/Mail/Draft.php	Type-4 MIME body import; toRfc822Stream() / append-replace edit model
test/Unit/ActiveSync/DraftSyncTest.php	Unit tests for RFC822 build, replace-on-edit, MIME envelope import

Related changes (other packages)

Deploy together with:

• horde/kronolith — ClientUid, Location, 16.0 instance export/import, listUids(hide_exceptions)
• horde/activesync — appointment 16.0 validation strip, recurrence protocol version, docs

Test plan

• php vendor/bin/phpunit --bootstrap core-tests-bootstrap.php vendor/horde/core/test/Unit/ActiveSync/DraftSyncTest.php — all tests pass
• EAS 16.0 calendar on device: recurring series initial sync includes bound exceptions as separate items (with kronolith deployed)
• EAS 16.0 mail: SendMail sends message and saves to Sent (device test @ single account)
• EAS 16.0 mail: server-created draft syncs down to client with IsDraft: 1 (device test)
• Draft edit upload from iOS not verified (client keeps edits local); server path covered by unit tests

Device testing notes (2026-06-16)

Area	Result
Calendar ClientUid / Location / recurrence instances	Pass (iPhone, EAS 16.0)
SendMail	Pass
Draft download (IMP → iPhone)	Pass
Draft edit upload (iPhone → IMP)	Not observed — iOS Mail limitation, not server regression