fix(bench): resolve packaged fixture root

[drewstone]

Problem

Compiled Bench chunks resolved ../.. above the installed package, so fixture-backed adapters tried to read node_modules/@tangle-network/fixtures/*.

Change

• Locate the Bench package root by its own package manifest from source or compiled files.
• Make the packed-consumer check load the ToolLLM fixture.
• Prepare @tangle-network/agent-bench 0.3.8.

Proof

• pnpm run verify:bench
• pnpm run lint && pnpm run test && pnpm run build && pnpm run typecheck && pnpm run verify:package && pnpm run docs:check
• Before: packed ToolLLM load failed with ENOENT at node_modules/@tangle-network/fixtures/toollm.json.
• After: packed consumer loaded 1/1 ToolLLM fixture and completed TypeScript 5.9.3 + 6.0.3 checks.

[tangletools]

✅ Auto-approved drewstone PR — 8c03ca8c

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 · 2026-07-24T22:20:21Z}