fix: port auto context memory to v2

[guslegend0510]

Port auto context memory to v2.

What changed:

• moved the auto-context extension to v2 AgentState / AgentStateStore
• wired context_reload through the hook/tool path
• added tests for compression, persistence, and offload reload

Validation:

• mvn -f agentscope-extensions/agentscope-extensions-mem/agentscope-extensions-autocontext-memory/pom.xml test

[codecov]

Codecov Report

❌ Patch coverage is 74.17012% with 249 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...ope/core/memory/autocontext/AutoContextMemory.java	69.14%	77 Missing and 64 partials ⚠️
...o/agentscope/core/memory/autocontext/MsgUtils.java	71.62%	11 Missing and 50 partials ⚠️
...scope/core/memory/autocontext/AutoContextHook.java	63.75%	15 Missing and 14 partials ⚠️
...cope/core/memory/autocontext/CompressionEvent.java	78.04%	0 Missing and 9 partials ⚠️
...tscope/core/memory/autocontext/PromptProvider.java	75.00%	0 Missing and 5 partials ⚠️
...ope/core/memory/autocontext/AutoContextConfig.java	97.43%	2 Missing ⚠️
...pe/core/memory/autocontext/ContextOffloadTool.java	92.85%	0 Missing and 2 partials ⚠️

📢 Thoughts on this report? Let us know!

[AgentScopeJavaBot]

🤖 AI Review

This PR ports the auto-context memory extension to v2, integrating with AgentState / AgentStateStore. The module adds automatic conversation compression (tool-group compression, large-message offloading, previous-round summarization, and current-round compression) via a Hook + Memory design. The code is well-structured with good separation of concerns and decent test coverage. However, there are several correctness and robustness issues: deleteMessage silently corrupts the original-memory buffer after compression, the LLM summarization call blocks while holding the instance monitor (risking lock-contention during slow model responses), and the config builder accepts any values without validation — all of which should be addressed before merge.

[AgentScopeJavaBot]

All blocking review comments have been addressed. 3 non-blocking suggestion(s) (minor/nit) remain open and may be addressed in a follow-up.