chore(release): prepare 0.131.1

[drewstone]

Summary

• Prepare @tangle-network/agent-runtime@0.131.1 from main commit cec06dfba037e1fd56442f81a5680a3d6abb9b33.
• Document MCP scalar and array text results, object-only structured results, and the official SDK regression proof.
• Regenerate the version-bearing fixtures and API catalog with the repository release command.
• Keep @tangle-network/agent-bench at 0.8.0.

Proof

• pnpm exec vitest run tests/mcp/tool-server.test.ts tests/mcp/tool-server-sdk.test.ts: 10/10 passed.
• pnpm test: 2,423 passed and 6 skipped across 205 files.
• pnpm run lint: 562 files checked.
• pnpm run typecheck: source and examples passed.
• pnpm run build: 149 files built.
• pnpm run verify:package: package identity and dependency checks passed.
• pnpm run docs:check: generated API and curated documentation are current.
• AGENT_RUNTIME_VERSION_BUMP_BASE=origin/main pnpm run check:version-bump: passed against cec06dfba037.
• pnpm install --frozen-lockfile: passed.
• gitleaks git --staged and gitleaks git --log-opts=origin/main..HEAD: no leaks found.
• git merge-tree --write-tree origin/main HEAD: 9022571eb13370ae978d1f601f7720225bc5d956.

This PR does not tag or publish the release.

[tangletools]

✅ Auto-approved drewstone PR — a01f7b8b

This PR was opened by the trusted drewstone account.
The full PR reviewer audit still runs separately and will publish findings if it detects issues.

_{tangletools · auto-approval · reason: drewstone_author · 2026-08-10T03:46:13Z}