add-jsonrpc-method

Add a JSON-RPC method

Input: a method name (eth_*, anvil_*, debug_*, or tevm_*), optionally its spec and the viem-style action name to expose on the client.

The whole JSON-RPC API lives in packages/actions. Follow the repository's documentation-driven order (CLAUDE.md): types and JSDoc first, a happy-path test, the implementation, then the full suite. Match the house pattern of a neighboring method in the same namespace (one file per item: the params type, the result type, the handler, the JSON-RPC procedure, the spec).

1. Read the spec. For eth_* use ethereum/execution-apis; for anvil_* use the anvil reference; for debug_* use geth's debug namespace. Decline a method whose semantics you cannot pin to a spec.
2. Types. Add <Method>Params.ts, <Method>Result.ts, and the <Method>JsonRpcRequest/Response/Procedure types beside the neighboring method. Full JSDoc with a complete @example that imports from tevm and runs; no ... placeholders.
3. Happy-path test. Add <method>Handler.spec.ts against a real createTevmNode() (no mocks). If the method reads chain state, use the snapshot transport from @tevm/test-utils so the test replays without network.
4. Implementation. <method>Handler.js in JavaScript with JSDoc, using the internal ethereumjs API through the node; <method>Procedure.js converting hex JSON-RPC params to the handler's params. Debug logging through the node's logger where a Logger is available.
5. Register the procedure in the request-handler dispatch table and, if the input named a client method, add the action to packages/memory-client and the decorator in packages/decorators. Update every request, response, params, result, handler, procedure, request-handler, and method-matrix union that represents neighboring methods; do not leave a method reachable through only one dispatch path.
6. Barrels. Re-export every new symbol by name through each index.js up to packages/actions/src/index.js, then tevm/actions/index.ts and, for client methods, tevm/memory-client/index.ts.
7. Regenerate the committed tevm emit (//tevm:dist --write, //tevm:types --write).
8. Docs. Add the method to the JSON-RPC reference page under docs/node/pages with one example.
9. Changeset. minor for the packages touched, one sentence naming the method.
10. Add a wire-contract test through the public JSON-RPC procedure or transport. Assert the exact encoded response and prove JSON.stringify(response) succeeds. No Promise, bigint, typed array, Error, or undefined may cross the boundary. Quantities are minimal hex, byte data is even-length, fixed words are left-padded, and spec-nullable fields use null.
11. Cover the method's negative or alternate form and assert its stable error class and numeric JSON-RPC code. When parity with Anvil/geth/viem is claimed, name the reference fixture in the test.
12. Run the actions test suite. Every test in the package passes, not only the new one.

PR title: ✨ feat(actions): add <method>. Body: what the method does, the spec link, and the packages it touches. Do not touch unrelated handlers.