refactor(ipc): generate preload forwarders from registry

tests/unit/preload-forwarders.test.ts

@@ -0,0 +1,64 @@
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+import { describe, expect, it } from "vitest";
+import {
+  IPC_CHANNELS,
+  PRELOAD_FORWARDERS,
+  mapPreloadInvokeArgs,
+  type PreloadPayloadSpec,
+} from "../../src/shared/contracts";
+
+describe("preload forwarders", () => {
+  it("keeps API methods and IPC channels unique", () => {
+    const apiNames = new Set<string>();
+    const channelNames = new Set<string>();
+    const ipcChannelKeys = new Set(Object.keys(IPC_CHANNELS));
+
+    for (const forwarder of PRELOAD_FORWARDERS) {
+      expect(ipcChannelKeys.has(forwarder.channel)).toBe(true);
+      expect(apiNames.has(forwarder.api)).toBe(false);
+      expect(channelNames.has(forwarder.channel)).toBe(false);
+      apiNames.add(forwarder.api);
+      channelNames.add(forwarder.channel);
+    }
+  });
+
+  it("maps zero, single, and object payloads", () => {
+    const noArgs = PRELOAD_FORWARDERS.find((forwarder) => forwarder.api === "loadSnapshot");
+    const singleArg = PRELOAD_FORWARDERS.find((forwarder) => forwarder.api === "openPath");
+    const objectArg = PRELOAD_FORWARDERS.find((forwarder) => forwarder.api === "importSkill");
+
+    expect(noArgs).toBeDefined();
+    expect(singleArg).toBeDefined();
+    expect(objectArg).toBeDefined();
+
+    expect(mapPreloadInvokeArgs(noArgs!.payload, [])).toEqual([]);
+    expect(mapPreloadInvokeArgs(singleArg!.payload, ["/tmp/output"])).toEqual(["/tmp/output"]);
+    expect(mapPreloadInvokeArgs(objectArg!.payload, ["company-1", "/skills/local"])).toEqual([
+      { companyId: "company-1", source: "/skills/local" },
+    ]);
+  });
+
+  it("rejects payload arity drift", () => {
+    const payload: PreloadPayloadSpec = { kind: "object", keys: ["companyId", "skillId"] };
+
+    expect(() => mapPreloadInvokeArgs(payload, ["company-1"])).toThrow(
+      "Invalid preload object argument count: expected 2, received 1",
+    );
+  });
+
+  it("keeps preload invoking through the shared registry", () => {
+    const preloadSource = readFileSync(join(process.cwd(), "src/preload/index.ts"), "utf8");
+    const staticChannelAccesses = [...preloadSource.matchAll(/IPC_CHANNELS\.([A-Za-z0-9_]+)/g)]
+      .map((match) => match[1]);
+
+    expect(staticChannelAccesses.sort()).toEqual([
+      "rendererEvent",
+      "rendererEvent",
+      "windowClose",
+      "windowIsMaximized",
+      "windowMaximize",
+      "windowMinimize",
+    ]);
+  });
+});