fix: skip compressed assistant tool calls

[guslegend0510]

背景

在 AutoContext 压缩场景下，assistant 消息会带有 _compress_meta 标记。原有逻辑在提取最近工具调用时，可能把这些压缩后的消息当成新的工具调用上下文，导致后续轮次恢复出的工具调用不正确，甚至出现重复执行风险。

修改内容

• 在 MessageUtils.extractRecentToolCalls() 中跳过带 _compress_meta 的 assistant 消息。
• 避免压缩消息污染“最近工具调用”的提取结果。
• 保持普通 assistant 消息和原有工具调用处理逻辑不变。

验证

• mvn -pl agentscope-core -am -Dtest=MessageUtilsTest test

Fixes #1482

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

❌ Patch coverage is 75.00000% with 3 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...ain/java/io/agentscope/core/util/MessageUtils.java	75.00%	0 Missing and 3 partials ⚠️

📢 Thoughts on this report? Let us know!

[LearningGp]

[guslegend0510]

@LearningGp 麻烦审核一下，谢谢

[AgentScopeJavaBot]

🤖 AI Review

This PR fixes a bug where MessageUtils.extractRecentToolCalls() could pick up tool calls from compressed assistant messages (those carrying _compress_meta metadata), leading to incorrect or duplicate tool call extraction in the AutoContext compression scenario. The fix is clean and well-scoped: it adds a continue guard to skip compressed messages when scanning backwards, and includes a new test class covering the main cases. The logic is correct and aligns with the issue description.