feat(hooks): add read-image-resizer hook

Intercepts Read tool output with image attachments and resizes to comply with Anthropic API limits (≤1568px long edge, ≤5MB). Only activates for Anthropic provider sessions and appends resize metadata (original/new resolution, token count) to tool output.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/plugin/tool-execute-after.ts

@@ -43,6 +43,7 @@ export function createToolExecuteAfterHandler(args: {
     await hooks.delegateTaskRetry?.["tool.execute.after"]?.(input, output)
     await hooks.atlasHook?.["tool.execute.after"]?.(input, output)
     await hooks.taskResumeInfo?.["tool.execute.after"]?.(input, output)
+    await hooks.readImageResizer?.["tool.execute.after"]?.(input, output)
     await hooks.hashlineReadEnhancer?.["tool.execute.after"]?.(input, output)
     await hooks.jsonErrorRecovery?.["tool.execute.after"]?.(input, output)
   }