refactor(context-window-recovery): split executor and storage into focused modules

Extract recovery strategies and storage management:
- recovery-strategy.ts, aggressive-truncation-strategy.ts
- summarize-retry-strategy.ts, target-token-truncation.ts
- empty-content-recovery.ts, message-builder.ts
- tool-result-storage.ts, storage-paths.ts, state.ts
- client.ts, tool-part-types.ts

src/hooks/anthropic-context-window-limit-recovery/client.ts

@@ -0,0 +1,33 @@
+export type Client = {
+  session: {
+    messages: (opts: {
+      path: { id: string }
+      query?: { directory?: string }
+    }) => Promise<unknown>
+    summarize: (opts: {
+      path: { id: string }
+      body: { providerID: string; modelID: string }
+      query: { directory: string }
+    }) => Promise<unknown>
+    revert: (opts: {
+      path: { id: string }
+      body: { messageID: string; partID?: string }
+      query: { directory: string }
+    }) => Promise<unknown>
+    prompt_async: (opts: {
+      path: { id: string }
+      body: { parts: Array<{ type: string; text: string }> }
+      query: { directory: string }
+    }) => Promise<unknown>
+  }
+  tui: {
+    showToast: (opts: {
+      body: {
+        title: string
+        message: string
+        variant: string
+        duration: number
+      }
+    }) => Promise<unknown>
+  }
+}