fix: revert ?? '' and defensive null checks across Socket files

PRs 124-129 replaced TypeScript non-null assertions (!) with optional
chaining (?.) and empty string defaults (?? ''). While defensive
programming is usually good, in Signal protocol and WhatsApp binary
node handling code these changes caused:

- Malformed JIDs with empty user components (e.g. @s.whatsapp.net)
- Silent device enumeration failures (messages skip recipients)
- Wrong own-device detection (message routing errors)
- Broken prekey count handling (prekey uploads silently skipped)
- Wrong retry count tracking in Signal protocol

These empty-string defaults are dangerous because Signal session
lookups fail for malformed JIDs, causing "SessionError: No sessions".

Reverted to original Baileys pattern using non-null assertions (!)
which match the upstream reference (infinitezap/Teste_InfiniteAPI).

Files fixed: messages-send.ts, messages-recv.ts, socket.ts, chats.ts,
groups.ts, communities.ts, business.ts

https://claude.ai/code/session_01XaA7GwNaB6azTHFYQ8WEpB

src/Socket/socket.ts

@@ -609,12 +609,8 @@ export const makeSocket = (config: SocketConfig) => {
 			},
 			content: [{ tag: 'count', attrs: {} }]
 		})
-		const countChild = getBinaryNodeChild(result, 'count')
-		if (!countChild) {
-			return 0
-		}
-
-		return +(countChild.attrs.value ?? 0)
+		const countChild = getBinaryNodeChild(result, 'count')!
+		return +countChild.attrs.value!
 	}
 
 	// Pre-key upload state management
@@ -1364,7 +1360,7 @@ export const makeSocket = (config: SocketConfig) => {
 			attrs: {
 				to: S_WHATSAPP_NET,
 				type: 'result',
-				id: stanza.attrs.id ?? ''
+				id: stanza.attrs.id!
 			}
 		}
 		await sendNode(iq)
@@ -1443,9 +1439,7 @@ export const makeSocket = (config: SocketConfig) => {
 		logger.info('opened connection to WA')
 		clearTimeout(qrTimer) // will never happen in all likelyhood -- but just in case WA sends success on first try
 
-		if (authState.creds.me) {
-			ev.emit('creds.update', { me: { ...authState.creds.me, lid: node.attrs.lid } })
-		}
+		ev.emit('creds.update', { me: { ...authState.creds.me!, lid: node.attrs.lid } })
 
 		ev.emit('connection.update', { connection: 'open' })
 
@@ -1468,23 +1462,13 @@ export const makeSocket = (config: SocketConfig) => {
 			const myLID = node.attrs.lid
 			process.nextTick(async () => {
 				try {
-					const me = authState.creds.me
-					if (!me) {
-						return
-					}
-
-					const myPN = me.id
+					const myPN = authState.creds.me!.id
 
 					// Store our own LID-PN mapping
 					await signalRepository.lidMapping.storeLIDPNMappings([{ lid: myLID, pn: myPN }])
 
 					// Create device list for our own user (needed for bulk migration)
-					const decoded = jidDecode(myPN)
-					if (!decoded) {
-						return
-					}
-
-					const { user, device } = decoded
+					const { user, device } = jidDecode(myPN)!
 					await authState.keys.set({
 						'device-list': {
 							[user]: [device?.toString() || '0']
@@ -1572,7 +1556,7 @@ export const makeSocket = (config: SocketConfig) => {
 			logger.debug({ name }, 'updated pushName')
 			sendNode({
 				tag: 'presence',
-				attrs: { name: name ?? '' }
+				attrs: { name: name! }
 			}).catch(err => {
 				logger.warn({ trace: err.stack }, 'error in sending presence update on name change')
 			})