fix(javascript): classify application input selection failures by cause

analyze_javascript_application reported every input-selection problem as
an artifact fault:

- a missing input path: "Artifact could not be read or written", with no
  path or reason;
- an unreadable selected directory: the same generic io failure;
- a regular file that is neither a directory nor an .asar, and a
  --artifact-format that contradicts the selection: "Artifact is invalid
  or has changed. Get a fresh copy and try again."

Report a missing path as an invalid input_path, an unreadable selection
as access_denied, a non-directory non-.asar file as unsupported_target
with the accepted inputs as remediation, and a contradicting format as an
invalid format with the observed kind as expected value. Failures inside
a selected artifact keep their existing classification.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/boundary/filesystem/javascriptApplicationInputSelection.test.ts

@@ -0,0 +1,102 @@
+import { chmod, mkdir, writeFile } from "node:fs/promises";
+import { join } from "node:path";
+
+import { describe, expect, it, onTestFinished } from "vitest";
+
+import { createTestTempDirectory } from "../../fixtures/temporaryDirectory.js";
+
+import { analyzeJavaScriptApplication } from "../../../src/application/javascript/JavaScriptApplicationService.js";
+import { projectAnalysisError } from "../../../src/domain/analysisErrorProjection.js";
+
+const analyzeFailure = async (input: Record<string, unknown>) => {
+  const result = await analyzeJavaScriptApplication(input);
+  if (result.ok) throw new Error("Expected the selection to be refused");
+  return projectAnalysisError(result.error);
+};
+
+const application = async () => {
+  const root = await createTestTempDirectory("rea-javascript-selection-");
+  const directory = join(root, "app");
+  await mkdir(directory);
+  await writeFile(join(directory, "index.js"), "module.exports = 1;\n");
+  return { root, directory };
+};
+
+describe("JavaScript application input selection", () => {
+  it("reports a missing input path as invalid input, not an artifact read failure", async () => {
+    const { root } = await application();
+    const missing = join(root, "missing");
+
+    expect(await analyzeFailure({ input_path: missing })).toMatchObject({
+      code: "invalid_request",
+      category: "invalid_input",
+      details: {
+        issues: [
+          {
+            path: ["input_path"],
+            reason: "invalid_value",
+            message: expect.stringContaining(missing),
+          },
+        ],
+      },
+    });
+  });
+
+  it("reports a file that is neither a directory nor an .asar as an unsupported target", async () => {
+    const { root } = await application();
+    const binary = join(root, "program");
+    await writeFile(binary, Buffer.from([0xcf, 0xfa, 0xed, 0xfe]));
+
+    expect(await analyzeFailure({ input_path: binary })).toMatchObject({
+      code: "unsupported_target",
+      category: "unsupported_target",
+      remediation: { action: expect.stringContaining(".asar") },
+      details: {
+        operation: "analyze_javascript_application",
+        path: binary,
+      },
+    });
+  });
+
+  it.each([
+    ["a directory", "directory", "asar"],
+    ["an .asar file", "asar", "directory"],
+  ] as const)(
+    "reports %s selected with a contradicting format as an invalid request",
+    async (_label, observed, format) => {
+      const { root, directory } = await application();
+      const selected =
+        observed === "directory" ? directory : join(root, "app.asar");
+      if (observed === "asar") await writeFile(selected, "not inspected");
+
+      expect(
+        await analyzeFailure({ input_path: selected, format }),
+      ).toMatchObject({
+        code: "invalid_request",
+        details: {
+          issues: [
+            {
+              path: ["format"],
+              reason: "invalid_value",
+              expected: ["auto", observed],
+            },
+          ],
+        },
+      });
+    },
+  );
+
+  it.skipIf(process.platform === "win32" || process.getuid?.() === 0)(
+    "reports an unreadable selected directory as a host access denial",
+    async () => {
+      const { directory } = await application();
+      await chmod(directory, 0o000);
+      onTestFinished(() => chmod(directory, 0o700));
+
+      expect(await analyzeFailure({ input_path: directory })).toMatchObject({
+        code: "access_denied",
+        details: { path: directory, system_code: "EACCES" },
+      });
+    },
+  );
+});