fix(core,cli,ci): harden runtime resolution + inline constant + smoke test (#458)

Guard buildHyperframesRuntimeScript() against missing entry.ts so it
returns null instead of crashing with esbuild stderr output. Add
getHyperframeRuntimeScript() that returns the pre-built IIFE as a
baked-in string constant — no esbuild, no file I/O, no import.meta.url.

Consolidate CLI runtime source resolution into a single module with
a clear priority chain: esbuild from source (dev) → inlined constant
(production) → pre-built artifact file (fallback).

Add CI smoke test that npm-packs the CLI, installs globally, runs
hyperframes preview, and asserts no stderr errors + runtime endpoint
returns JS.

Bump version to 0.4.16.

packages/core/src/index.ts

@@ -139,6 +139,7 @@ export {
   HYPERFRAME_CONTROL_ACTIONS,
   type HyperframeControlAction,
 } from "./inline-scripts/runtimeContract";
+export { getHyperframeRuntimeScript } from "./generated/runtime-inline";
 export {
   buildHyperframesRuntimeScript,
   type HyperframesRuntimeBuildOptions,