#5: F2 sub-project 2 - IMAP SEARCH, EXPUNGE, COPY, MOVE

Adds the second F2 sub-project on top of the merged IMAP core: full
SEARCH criteria matching (flags, dates, size, headers, body/text,
NOT/OR), EXPUNGE (soft-delete via expunged_at), COPY, and MOVE (RFC
6851, advertised via CapMove/CapUIDPlus). Verified end-to-end with a
real go-imap/v2 client against embedded Postgres.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

services/protocols/internal/application/port/copy_repository.go

@@ -0,0 +1,21 @@
+package port
+
+import "context"
+
+// CopiedMessage records one message's UID before and after a COPY/MOVE.
+type CopiedMessage struct {
+	SourceUID uint32
+	DestUID   uint32
+}
+
+// CopyRepository duplicates messages into another folder, preserving their
+// blob reference (content-hash dedup - PLAN.md section 9) and flags.
+type CopyRepository interface {
+	// CopyMessages copies each message identified by (sourceFolderID, uid)
+	// in uids into destFolderID, allocating a new UID in the destination
+	// per message, preserving flags, and incrementing the destination
+	// folder's total_count/unread_count and the destination mailbox's
+	// used_bytes accordingly. Returns one CopiedMessage per input uid, in
+	// the same order as uids.
+	CopyMessages(ctx context.Context, sourceFolderID string, uids []uint32, destFolderID string) ([]CopiedMessage, error)
+}