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/index.ts

@@ -3,3 +3,6 @@ export type { AnthropicContextWindowLimitRecoveryOptions } from "./recovery-hook
 export type { AutoCompactState, ParsedTokenLimitError, TruncateState } from "./types"
 export { parseAnthropicTokenLimitError } from "./parser"
 export { executeCompact, getLastAssistant } from "./executor"
+export * from "./state"
+export * from "./message-builder"
+export * from "./recovery-strategy"