Add LangChain JS, LangGraph, and Mastra adapter packages

[ethanj]

Summary

Add three new adapter packages that integrate AtomicMemory into LangChain JS, LangGraph JS, and Mastra, alongside a new setup host CLI command and expanded plugin manifest test coverage.

Changes

Adapters

• @atomicmemory/langchain — searchMemory() / ingestTurn() helpers usable inside any LCEL chain or callback, plus createMemoryTools() producing memory_search and memory_ingest @langchain/core/tools-compatible instances with scope fixed at factory time.
• @atomicmemory/langgraph — createMemoryRetrieveNode() and createMemoryIngestNode() factories emitting plain (state) => Partial<state> async functions registerable via .addNode(). Fully generic over the caller's state type; never imports @langchain/langgraph at runtime.
• @atomicmemory/mastra — createMemoryTools() producing memory_search and memory_ingest Mastra createTool() instances, plus the same framework-agnostic searchMemory() / ingestTurn() helpers.
• All three adapters: default atomicmemory:context formatter with explicit "reference, not instructions" header; system role excluded from ingestTurn() by default with opt-in includeRoles; scope bound at factory time so agents cannot rebind across users.
• Full unit test suites for search, ingest, tools/nodes, and fake MemoryClient fixtures in each adapter.

CLI

• Add setup host command (packages/cli/src/commands/setup/host/) with host-configuration templates and tests.
• Register the new command in packages/cli/src/commands/registry.ts.
• Update CLI spec and README to document the new command.

Plugin test coverage

• Add plugin manifest regression tests for the Codex and Cursor plugins.
• Add package-files integrity tests for the claude-code and openclaw plugins.
• Add packed-bin test for the MCP server.

Why

LangChain JS, LangGraph, and Mastra are the most widely adopted JavaScript agent frameworks. Without first-party adapters, integrating AtomicMemory requires users to write their own wiring for MemoryClient scope binding, message filtering, and context rendering — including subtle safety concerns like system-message exclusion and prompt-injection mitigations in the context block. These adapters provide a tested, opinionated path while remaining thin enough to fit any existing graph or agent configuration.

Validation

Each adapter ships with unit tests covering: query passthrough, scope-binding invariance (factory scope cannot be overridden by the agent), null-context propagation on empty results, system-role exclusion by default, includeRoles opt-in, custom formatter override, and the no-memories sentinel string. Plugin manifest and package-files tests guard against packaging regressions across the Codex, Cursor, claude-code, and openclaw plugins.