fix: preserve setup diagnostics and clean Knip config

knip.json

@@ -1,18 +1,7 @@
 {
   "$schema": "./node_modules/knip/schema.json",
-  "entry": [
-    "src/main.ts",
-    "src/cli.ts",
-    "scripts/rea.mjs",
-    "scripts/scan-todos.mjs"
-  ],
-  "project": [
-    "src/**/*.ts",
-    "tests/**/*.ts",
-    "scripts/**/*.mjs",
-    "vitest.config.ts"
-  ],
-  "ignore": ["dist/**", "docs/**", ".codex/**", ".devin/**"],
+  "entry": ["src/main.ts", "src/cli.ts"],
+  "project": ["src/**/*.ts", "tests/**/*.ts", "scripts/**/*.mjs"],
   "ignoreDependencies": [],
   "rules": {
     "files": "error",

src/application/SetupInstallFailure.ts

@@ -6,7 +6,11 @@ export type SetupFailureCode =
   | "launcher_missing"
   | "runtime_dependency_unavailable"
   | "unsupported_hopper_build"
-  | "setup_cancelled";
+  | "setup_cancelled"
+  | "destination_exists"
+  | "mount_failed"
+  | "bundle_invalid"
+  | "copy_failed";
 
 export type SetupHopperInstallResult =
   | { readonly status: "installed"; readonly launcherPath: string }
@@ -84,6 +88,34 @@ export const setupInstallFailure = (
         remediation:
           "Setup was cancelled before Hopper was installed. Rerun rea setup when ready.",
       };
+    case "destination_exists":
+      return {
+        status: "failed",
+        code: "destination_exists",
+        remediation:
+          "The Hopper installation destination already exists and was not replaced. Reuse the existing installation or move it aside, then rerun rea setup.",
+      };
+    case "mount":
+      return {
+        status: "failed",
+        code: "mount_failed",
+        remediation:
+          "The verified Hopper disk image could not be mounted. Eject any stale Hopper image, check local disk access, then rerun rea setup.",
+      };
+    case "bundle":
+      return {
+        status: "failed",
+        code: "bundle_invalid",
+        remediation:
+          "The mounted package did not contain the expected Hopper application bundle. Retry setup; if it repeats, update REA before installing.",
+      };
+    case "copy":
+      return {
+        status: "failed",
+        code: "copy_failed",
+        remediation:
+          "The verified Hopper application could not be copied to the installation destination. Check destination permissions and free space, then rerun rea setup.",
+      };
     default:
       return {
         status: "failed",

src/config.ts

@@ -108,9 +108,12 @@ const parseStringArray = (
     return parsed.success
       ? ok(parsed.data)
       : err(
-          new ConfigurationError(`${name} must encode an array of strings`, {
-            cause: parsed.error,
-          }),
+          new ConfigurationError(
+            parsed.error.issues.some(({ code }) => code === "too_big")
+              ? `${name} must encode at most 128 strings`
+              : `${name} must encode an array of strings`,
+            { cause: parsed.error },
+          ),
         );
   } catch (cause: unknown) {
     return err(new ConfigurationError(`${name} must be valid JSON`, { cause }));

tests/config.test.ts

@@ -125,6 +125,19 @@ describe("runtime configuration", () => {
     },
   );
 
+  it("reports the configured string-array size limit", () => {
+    const result = parseConfig({
+      REA_INVESTIGATION_INPUT_ROOTS_JSON: JSON.stringify(
+        Array.from({ length: 129 }, (_, index) => `/input/${String(index)}`),
+      ),
+    });
+    expect(result.ok).toBe(false);
+    if (!result.ok)
+      expect(result.error.message).toBe(
+        "REA_INVESTIGATION_INPUT_ROOTS_JSON must encode at most 128 strings",
+      );
+  });
+
   it("parses supported log levels and rejects unknown levels", () => {
     const configured = parseConfig({ REA_LOG_LEVEL: "debug" });
     expect(configured.ok && configured.value.logLevel).toBe("debug");

tests/setupInstallFailure.test.ts

@@ -19,6 +19,10 @@ describe("setup installer failure projection", () => {
     ["runtime_dependencies", "runtime_dependency_unavailable"],
     ["unsupported_hopper_build", "unsupported_hopper_build"],
     ["cancelled", "setup_cancelled"],
+    ["destination_exists", "destination_exists"],
+    ["mount", "mount_failed"],
+    ["bundle", "bundle_invalid"],
+    ["copy", "copy_failed"],
   ] as const)("maps %s to %s", (reason, code) => {
     const result = setupInstallFailure(reason as HopperInstallFailureReason);
     expect(result).toMatchObject({ status: "failed", code });