fix: address 5 SDK compatibility issues from Cubic round 8

- P1: Use compacted timestamp check instead of nonexistent truncated
  field in target-token-truncation.ts
- P1: Use defensive (response.data ?? response) pattern in
  hook-message-injector/injector.ts to match codebase convention
- P2: Filter by tool type in countTruncatedResultsFromSDK to avoid
  counting non-tool compacted parts
- P2: Treat thinking/meta-only messages as empty in both
  empty-content-recovery-sdk.ts and message-builder.ts to align
  SDK path with file-based logic

src/features/hook-message-injector/injector.ts

@@ -64,7 +64,7 @@ export async function findNearestMessageWithFieldsFromSDK(
 ): Promise<StoredMessage | null> {
   try {
     const response = await client.session.messages({ path: { id: sessionID } })
-    const messages = (response.data ?? []) as SDKMessage[]
+    const messages = ((response.data ?? response) as unknown as SDKMessage[]) ?? []
 
     for (let i = messages.length - 1; i >= 0; i--) {
       const stored = convertSDKMessageToStoredMessage(messages[i])
@@ -97,7 +97,7 @@ export async function findFirstMessageWithAgentFromSDK(
 ): Promise<string | null> {
   try {
     const response = await client.session.messages({ path: { id: sessionID } })
-    const messages = (response.data ?? []) as SDKMessage[]
+    const messages = ((response.data ?? response) as unknown as SDKMessage[]) ?? []
 
     for (const msg of messages) {
       const stored = convertSDKMessageToStoredMessage(msg)

src/hooks/anthropic-context-window-limit-recovery/empty-content-recovery-sdk.ts

@@ -40,8 +40,9 @@ function messageHasContentFromSDK(message: SDKMessage): boolean {
     return true
   }
 
-  // Messages with only thinking/meta parts are NOT empty — they have content
-  return hasIgnoredParts
+  // Messages with only thinking/meta parts are treated as empty
+  // to align with file-based logic (messageHasContent)
+  return false
 }
 
 function getSdkMessages(response: unknown): SDKMessage[] {

src/hooks/anthropic-context-window-limit-recovery/message-builder.ts

@@ -51,8 +51,9 @@ function messageHasContentFromSDK(message: SDKMessage): boolean {
     return true
   }
 
-  // Messages with only thinking/meta parts are NOT empty — they have content
-  return hasIgnoredParts
+  // Messages with only thinking/meta parts are treated as empty
+  // to align with file-based logic (messageHasContent)
+  return false
 }
 
 async function findEmptyMessageIdsFromSDK(

src/hooks/anthropic-context-window-limit-recovery/target-token-truncation.ts

@@ -10,8 +10,10 @@ interface SDKToolPart {
 	id: string
 	type: string
 	tool?: string
-	state?: { output?: string }
-	truncated?: boolean
+	state?: {
+		output?: string
+		time?: { start?: number; end?: number; compacted?: number }
+	}
 	originalSize?: number
 }
 
@@ -81,7 +83,7 @@ export async function truncateUntilTargetTokens(
 
 		const results: import("./tool-part-types").ToolResultInfo[] = []
 		for (const [key, part] of toolPartsByKey) {
-			if (part.type === "tool" && part.state?.output && !part.truncated && part.tool) {
+			if (part.type === "tool" && part.state?.output && !part.state?.time?.compacted && part.tool) {
 				results.push({
 					partPath: "",
 					partId: part.id,

src/hooks/anthropic-context-window-limit-recovery/tool-result-storage-sdk.ts

@@ -104,7 +104,7 @@ export async function countTruncatedResultsFromSDK(
     for (const msg of messages) {
       if (!msg.parts) continue
       for (const part of msg.parts) {
-        if (part.state?.time?.compacted) count++
+        if (part.type === "tool" && part.state?.time?.compacted) count++
       }
     }