* test(memory): pin the memory guides to the layout DeerMem resolves
The en and zh harness guides still document the pre-abstraction storage
shape, and nothing in CI reads prose, so the drift stayed invisible.
Derive the per-user manifest and per-agent facts paths from
memory_file_path()/agent_facts_directory() and take the allowed memory:
top-level keys from the public MemoryConfig model.
* docs(harness): scope memory docs per user and nest DeerMem knobs
Both guides claimed a shared {base_dir}/memory.json plus one memory.json
per agent; DeerMem keeps one manifest per user and puts agent state in a
facts directory beside it. The zh Configuration example also still showed
DeerMem-private keys at the memory top level, which config.example.yaml
and the en twin already place under backend_config.
* docs(memory): align per-agent facts overviews in both languages
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
