Add PraisonAI compute provider example

[opencolin]

Adds examples/praisonai-tenki: PraisonAI's Tenki compute provider gives an agent team one shared microVM (PraisonAIAgents(..., compute="tenki")), so files written by one agent are there for the next.

Not in a PyPI release yet — the provider (#3242) and the shared team/workflow wiring (#3949) both merged 2026-08-14, after the latest releases — so requirements pin both packages to the same git commit (mixing old praisonaiagents with new praisonai breaks the compute="tenki" lookup; README warns). verify.py resolves "tenki" through the real compute bridge, provisions a microVM, runs a command, round-trips a file, shuts down. Passed live.

One upstream sharp edge found and documented: Tenki's stock image has no /workspace and the shared-workspace tools don't create it — README gives the workarounds.

Root README: PraisonAI row in Agent frameworks.

🤖 Generated with Claude Code

[tenki-reviewer]

Review complete. No blocking issues — approved ✅; 1 nitpick below.

🧹 Nitpicks (1) — 🟢 1 low

• 🟢 finally block raises NameError when provisioning fails (verify.py:112) — verify.py's finally block at line 112-113 calls asyncio.run(compute.shutdown(info.instance_id)) unconditionally, but info is only bound by asyncio.run(compute.provision(config)) at line 73.

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This PR introduces a new examples/praisonai-tenki/ example showing how to run a PraisonAI agent inside a Tenki Firecracker microVM sandbox, plus a smoke-test script that provisions, uploads files, executes, downloads, and shuts down the sandbox. The README and requirements.txt are docs/config only.

Files	Change
README.md	Adds an index link to the new praisonai-tenki example.
examples/praisonai-tenki/README.md	Documents setup, env vars, and usage for the example.
examples/praisonai-tenki/requirements.txt	Pins the Python deps (tenki and praisonai) for the verify script.
examples/praisonai-tenki/verify.mjs	Node smoke test mirroring the Python flow against the Tenki sandbox.
examples/praisonai-tenki/verify.py	Python smoke test; its unguarded finally shutdown dereferences info when provisioning fails.

_{Reviewed commit: 04ab965}