feat: add client tool execution guard

[blove]

Summary

• Add the middleware client-tool execution store contract plus an in-memory implementation for deterministic dedup state.
• Add LangGraph helpers to record inbound client tool results, filter duplicate result messages, and look up prior executions for reload reconciliation.
• Add a caller-supplied Postgres tagged-SQL store, exported schema, README guidance, and regenerated middleware API docs.

Test Plan

• npx vitest run src/client-tool-execution-store.spec.ts --config vite.config.mts
• npx vitest run src/client-tool-result-guard.spec.ts --config vite.config.mts
• npx vitest run src/postgres-client-tool-execution-store.spec.ts --config vite.config.mts
• npm run generate-api-docs
• npx nx test middleware
• npx nx lint middleware
• npx nx build middleware
• npx nx run-many -t build --projects=chat,langgraph,ag-ui,render,a2ui,licensing,telemetry --configuration=production
• node scripts/check-dx-coverage.mjs
• git diff --check

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Project	Deployment	Actions	Updated (UTC)
threadplane	Ready	Preview, Comment	Jul 8, 2026 4:51pm

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