feat: wire context-window-recovery callers to async SDK/HTTP variants on SQLite

- empty-content-recovery: isSqliteBackend() branch delegating to extracted
  empty-content-recovery-sdk.ts with SDK message scanning
- message-builder: sanitizeEmptyMessagesBeforeSummarize now async with SDK path
  using replaceEmptyTextPartsAsync/injectTextPartAsync
- target-token-truncation: truncateUntilTargetTokens now async with SDK path
  using findToolResultsBySizeFromSDK/truncateToolResultAsync
- aggressive-truncation-strategy: passes client to truncateUntilTargetTokens
- summarize-retry-strategy: await sanitizeEmptyMessagesBeforeSummarize
- client.ts: derive Client from PluginInput['client'] instead of manual defs
- executor.test.ts: .mockReturnValue() → .mockResolvedValue() for async fns
- storage.test.ts: add await for async truncateUntilTargetTokens

src/hooks/anthropic-context-window-limit-recovery/aggressive-truncation-strategy.ts

@@ -25,12 +25,13 @@ export async function runAggressiveTruncationStrategy(params: {
     targetRatio: TRUNCATE_CONFIG.targetTokenRatio,
   })
 
-  const aggressiveResult = truncateUntilTargetTokens(
+  const aggressiveResult = await truncateUntilTargetTokens(
     params.sessionID,
     params.currentTokens,
     params.maxTokens,
     TRUNCATE_CONFIG.targetTokenRatio,
     TRUNCATE_CONFIG.charsPerToken,
+    params.client,
   )
 
   if (aggressiveResult.truncatedCount <= 0) {