test(native): pin IDA and Kuna in the dispatch fallback acceptance test

The darwin-only acceptance test passes the caller's environment to the CLI
and points only Hopper, Ghidra and Java at missing paths. On macOS the
list_names fallback has four candidates (ghidra, hopper, ida, kuna), so a
REA_IDA_MCP_CONFIG or REA_KUNA_COMMAND set in the developer's shell still
reaches it: with REA_KUNA_COMMAND set, kuna is no longer rejected as
not_configured. Point both at missing paths, as
tests/acceptance/nativeDispatchSnapshot.test.ts does, so the test always
exercises the unavailable fallback.

Signed-off-by: Zhaowei Gu <83746079+zw-g@users.noreply.github.com>

Refs #7651

Co-Authored-By: gensokyo-dev <342580529+gensokyo-dev@users.noreply.github.com>

tests/acceptance/nativeDispatchFallbackFailure.test.ts

@@ -29,6 +29,9 @@ cliTest.skipIf(process.platform !== "darwin")(
           HOPPER_LAUNCHER_PATH: join(root, "missing-hopper"),
           GHIDRA_INSTALL_DIR: join(root, "missing-ghidra"),
           JAVA_HOME: join(root, "missing-java"),
+          REA_IDA_MCP_CONFIG: join(root, "missing-ida-mcp.json"),
+          REA_KUNA_COMMAND: join(root, "missing-kuna"),
+          REA_KUNA_CACHE_DIR: join(root, "missing-kuna-cache"),
         },
       });
       expect(result.exitCode).toBe(1);