fix(hooks): improve session recovery for empty content messages

- Extract message index from Anthropic error messages (messages.N format)
- Sort messages by time.created instead of id for accurate ordering
- Remove last message skip logic that prevented recovery
- Prioritize recovery targets: index-matched > failedMsg > all empty
- Add error logging for debugging recovery failures

Fixes issue where 'messages.83: all messages must have non-empty content' errors were not being recovered properly due to incorrect message ordering and overly restrictive filtering.

🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

src/hooks/session-recovery/storage.ts

@@ -42,7 +42,12 @@ export function readMessages(sessionID: string): StoredMessageMeta[] {
     }
   }
 
-  return messages.sort((a, b) => a.id.localeCompare(b.id))
+  return messages.sort((a, b) => {
+    const aTime = a.time?.created ?? 0
+    const bTime = b.time?.created ?? 0
+    if (aTime !== bTime) return aTime - bTime
+    return a.id.localeCompare(b.id)
+  })
 }
 
 export function readParts(messageID: string): StoredPart[] {
@@ -117,13 +122,9 @@ export function findEmptyMessages(sessionID: string): string[] {
   const messages = readMessages(sessionID)
   const emptyIds: string[] = []
 
-  for (let i = 0; i < messages.length; i++) {
-    const msg = messages[i]
+  for (const msg of messages) {
     if (msg.role !== "assistant") continue
 
-    const isLastMessage = i === messages.length - 1
-    if (isLastMessage) continue
-
     if (!messageHasContent(msg.id)) {
       emptyIds.push(msg.id)
     }
@@ -132,6 +133,18 @@ export function findEmptyMessages(sessionID: string): string[] {
   return emptyIds
 }
 
+export function findEmptyMessageByIndex(sessionID: string, targetIndex: number): string | null {
+  const messages = readMessages(sessionID)
+  
+  if (targetIndex < 0 || targetIndex >= messages.length) return null
+
+  const targetMsg = messages[targetIndex]
+  if (targetMsg.role !== "assistant") return null
+  if (messageHasContent(targetMsg.id)) return null
+
+  return targetMsg.id
+}
+
 export function findFirstEmptyMessage(sessionID: string): string | null {
   const emptyIds = findEmptyMessages(sessionID)
   return emptyIds.length > 0 ? emptyIds[0] : null