fix: address codex/copilot review on view-once send/recv

P1 (messages-recv.ts): remove early return for <unavailable type="view_once"/>.
decryptMessageNode already handles this gracefully — decode-wa-message.ts sets
fullMessage.key.isViewOnce=true and skips the CIPHERTEXT stub (line 464).
The early return was preventing upsertMessage from emitting an event to consumers,
making view-once sends from the primary phone invisible on linked devices.

P2 (messages-send.ts): restrict isViewOnceMsg detection to actual view-once media.
Previously checked only for the presence of viewOnceMessage* wrappers, which are
also used by buttons/lists/carousels (non-view-once). Now unwraps the inner message
and checks imageMessage.viewOnce / videoMessage.viewOnce / audioMessage.viewOnce,
consistent with the detection in decode-wa-message.ts. Prevents companion DSM
filtering from incorrectly applying to interactive messages.

P3 (messages-send.ts): move assertSessions to use only the recipients actually
encrypted for. For view-once, omitted companions no longer cause assertSessions
to fail or do unnecessary session validation work.

Co-Authored-By: Renato Alcara

src/Socket/messages-send.ts

@@ -1277,21 +1277,48 @@ export const makeMessagesSocket = (config: SocketConfig) => {
 					: otherRecipients
 				const effectiveAllRecipients = [...effectiveMeRecipients, ...effectiveOtherRecipients]
 
-				await assertSessions(effectiveAllRecipients)
+				// P2: detect actual view-once media by checking inner message's viewOnce flag.
+				// viewOnceMessage wrapper is also used for interactive messages (buttons, lists, etc)
+				// which do NOT carry viewOnce=true on the media — those must NOT be filtered.
+				const viewOnceInner =
+					message.viewOnceMessageV2?.message ||
+					message.viewOnceMessage?.message ||
+					message.viewOnceMessageV2Extension?.message
+				const isViewOnceMsg = !!(
+					viewOnceInner?.imageMessage?.viewOnce ||
+					viewOnceInner?.videoMessage?.viewOnce ||
+					viewOnceInner?.audioMessage?.viewOnce
+				)
+
+				// For view-once: only send DSM to primary phone (device=0).
+				// Companion devices (device>0) are omitted — WA server generates
+				// <unavailable type="view_once"/> for them automatically.
+				// Sending explicit <unavailable> from a companion is rejected by the server.
+				const viewOnceMeRecipients = isViewOnceMsg
+					? effectiveMeRecipients.filter(jid => !jidDecode(jid)?.device)
+					: effectiveMeRecipients
+
+				// P3: assert sessions only for recipients we actually encrypt for.
+				// For view-once, companions are omitted — asserting their sessions is wasteful
+				// and could block the send if a companion session is corrupted.
+				await assertSessions([...viewOnceMeRecipients, ...effectiveOtherRecipients])
 
 				const [
 					{ nodes: meNodes, shouldIncludeDeviceIdentity: s1 },
 					{ nodes: otherNodes, shouldIncludeDeviceIdentity: s2 }
 				] = await Promise.all([
 					// For own devices: use DSM (deviceSentMessage) wrapper
-					createParticipantNodes(effectiveMeRecipients, meMsg || message, extraAttrs),
+					createParticipantNodes(viewOnceMeRecipients, meMsg || message, extraAttrs),
 					createParticipantNodes(effectiveOtherRecipients, message, extraAttrs)
 				])
 				participants.push(...meNodes)
 				participants.push(...otherNodes)
 
-				if (effectiveMeRecipients.length > 0 || effectiveOtherRecipients.length > 0) {
-					extraAttrs['phash'] = generateParticipantHashV2(effectiveAllRecipients)
+				const phashRecipients = isViewOnceMsg
+					? [...viewOnceMeRecipients, ...effectiveOtherRecipients]
+					: effectiveAllRecipients
+				if (phashRecipients.length > 0) {
+					extraAttrs['phash'] = generateParticipantHashV2(phashRecipients)
 				}
 
 				shouldIncludeDeviceIdentity = shouldIncludeDeviceIdentity || s1 || s2
@@ -1897,6 +1924,15 @@ export const makeMessagesSocket = (config: SocketConfig) => {
 	}
 
 	const getMediaType = (message: proto.IMessage) => {
+		// For view-once media, unwrap the viewOnceMessage wrapper before checking media type
+		const inner =
+			message.viewOnceMessage?.message ||
+			message.viewOnceMessageV2?.message ||
+			message.viewOnceMessageV2Extension?.message
+		if (inner) {
+			return getMediaType(inner)
+		}
+
 		if (message.imageMessage) {
 			return 'image'
 		} else if (message.videoMessage) {

src/Utils/decode-wa-message.ts

@@ -392,6 +392,23 @@ export const decryptMessageNode = (
 						} else {
 							fullMessage.message = msg
 						}
+
+						// Detect view-once media on stanza 1 received by linked device.
+						// viewOnceMessage wrapper is also used for interactive messages
+						// (interactiveMessage, listMessage, nativeFlowMessage) -- those do NOT have
+						// imageMessage.viewOnce / videoMessage.viewOnce / audioMessage.viewOnce = true.
+						// Only real view-once media carries viewOnce: true on the inner media message.
+						const viewOnceInner =
+							msg.viewOnceMessage?.message ||
+							msg.viewOnceMessageV2?.message ||
+							msg.viewOnceMessageV2Extension?.message
+						if (
+							viewOnceInner?.imageMessage?.viewOnce ||
+							viewOnceInner?.videoMessage?.viewOnce ||
+							viewOnceInner?.audioMessage?.viewOnce
+						) {
+							fullMessage.key.isViewOnce = true
+						}
 					} catch (err: any) {
 						// Check if this is a final failure after all retries exhausted
 						const isRetryExhausted = err instanceof RetryExhaustedError