fix(compaction): validate recovered agent config state

Retry compaction recovery when model or tool state is still incomplete, and treat reasoning or tool-only assistant progress as valid output so no-text tail recovery does not misfire.

src/hooks/compaction-context-injector/recovery-prompt-config.ts

@@ -0,0 +1,76 @@
+import type { CompactionAgentConfigCheckpoint } from "../../shared/compaction-agent-config-checkpoint"
+
+export type RecoveryPromptConfig = CompactionAgentConfigCheckpoint & {
+  agent: string
+}
+
+function isCompactionAgent(agent: string | undefined): boolean {
+  return agent?.trim().toLowerCase() === "compaction"
+}
+
+function matchesExpectedModel(
+  actualModel: CompactionAgentConfigCheckpoint["model"],
+  expectedModel: CompactionAgentConfigCheckpoint["model"],
+): boolean {
+  if (!expectedModel) {
+    return true
+  }
+
+  return (
+    actualModel?.providerID === expectedModel.providerID &&
+    actualModel.modelID === expectedModel.modelID
+  )
+}
+
+function matchesExpectedTools(
+  actualTools: CompactionAgentConfigCheckpoint["tools"],
+  expectedTools: CompactionAgentConfigCheckpoint["tools"],
+): boolean {
+  if (!expectedTools) {
+    return true
+  }
+
+  if (!actualTools) {
+    return false
+  }
+
+  const expectedEntries = Object.entries(expectedTools)
+  if (expectedEntries.length !== Object.keys(actualTools).length) {
+    return false
+  }
+
+  return expectedEntries.every(
+    ([toolName, isAllowed]) => actualTools[toolName] === isAllowed,
+  )
+}
+
+export function createExpectedRecoveryPromptConfig(
+  checkpoint: Pick<RecoveryPromptConfig, "agent"> & CompactionAgentConfigCheckpoint,
+  currentPromptConfig: CompactionAgentConfigCheckpoint,
+): RecoveryPromptConfig {
+  const model = checkpoint.model ?? currentPromptConfig.model
+  const tools = checkpoint.tools ?? currentPromptConfig.tools
+
+  return {
+    agent: checkpoint.agent,
+    ...(model ? { model } : {}),
+    ...(tools ? { tools } : {}),
+  }
+}
+
+export function isPromptConfigRecovered(
+  actualPromptConfig: CompactionAgentConfigCheckpoint,
+  expectedPromptConfig: RecoveryPromptConfig,
+): boolean {
+  const actualAgent = actualPromptConfig.agent
+  const agentMatches =
+    typeof actualAgent === "string" &&
+    !isCompactionAgent(actualAgent) &&
+    actualAgent.toLowerCase() === expectedPromptConfig.agent.toLowerCase()
+
+  return (
+    agentMatches &&
+    matchesExpectedModel(actualPromptConfig.model, expectedPromptConfig.model) &&
+    matchesExpectedTools(actualPromptConfig.tools, expectedPromptConfig.tools)
+  )
+}