bug(memos-local-plugin): L3 abstraction rejects salvageable structured outputs too aggressively

[liuhaibin0528]

Pre-submission checklist | 提交前检查

• I have searched existing issues and this hasn't been mentioned before | 我已搜索现有问题，确认此问题尚未被提及
• I have read the project documentation and confirmed this issue doesn't already exist | 我已阅读项目文档并确认此问题尚未存在
• This issue is specific to MemOS and not a general software issue | 该问题是针对 MemOS 的，而不是一般软件问题

Bug Description | 问题描述

apps/memos-local-plugin currently rejects many otherwise-usable L3 abstraction drafts too early when the model returns partially structured JSON.

In practice, I saw repeated world_model_generate failures where the payload still had usable body / domain_tags / string items, but the validator aborted because:

• title was empty
• inference / constraints were not arrays
• some list entries came back as strings or { body: ... }

This causes the L3 pipeline to fail hard instead of salvaging a draft and letting downstream validation decide whether it is good enough to persist.

How to Reproduce | 如何重现

1. Use apps/memos-local-plugin with an OpenAI-compatible structured-output model that is not perfectly strict on every generation.
2. Let the plugin accumulate enough traces/policies to trigger world_model_generate.
3. Check logs for failures like:
   • l3.abstraction: 'title' must be a non-empty string
   • l3.abstraction: 'inference' must be an array
   • l3.abstraction: 'constraints' must be an array

Environment | 环境信息

• MemOS version: main as of 2026-05-09
• Plugin: apps/memos-local-plugin
• Example model that reproduced this: glm-4-flashx-250414 via OpenAI-compatible API

Additional Context | 其他信息

This is not only a model-quality issue.

The current parser is strict enough that slightly malformed but semantically usable drafts are discarded wholesale. A more resilient normalization path for:

• fallback title derivation
• string / object list entry coercion
• string tag splitting

would make L3 much less fragile across providers.

I did not open a PR for this yet because it changes parser policy, not just transport/runtime behavior.

Willingness to Implement | 实现意愿

• I'm willing to implement this myself | 我愿意自己解决
• I would like someone else to implement this | 我希望其他人来解决