fix(artifacts): never treat a directory named *.map as a source map (#4131)

Artifact inventory decided source-map edges from the `.map` path suffix,
so an archive directory such as `main.js.map/` received a maps-source
edge whose parent was the sibling `main.js`, although the same
occurrence was classified as a directory container. Edge construction
now uses the occurrence's own artifact_kind, and the duplicate suffix
rule in relationFor is removed; such directories are contained by their
parent, and real source-map files keep maps-source.

Fixes #3909

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

src/artifacts/inventory/ArtifactGraphConstruction.test.ts

@@ -121,6 +121,43 @@ describe("source-map artifact relationships", () => {
       );
     },
   );
+
+  it("keeps a directory named like a source map contained by its parent", () => {
+    const archive = createOccurrence(entry("app", "directory"), "app", null);
+    archive.artifact_id = contentId("1");
+    const script = createOccurrence(
+      entry("app/main.js", "file"),
+      "app/main.js",
+      archive.occurrence_id,
+    );
+    script.artifact_id = contentId("2");
+    const directory = createOccurrence(
+      entry("app/main.js.map", "directory"),
+      "app/main.js.map",
+      archive.occurrence_id,
+    );
+    directory.artifact_id = contentId("3");
+
+    const { edges, limitations } = createArtifactEdges(contentId("4"), [
+      archive,
+      script,
+      directory,
+    ]);
+
+    expect(directory).toMatchObject({
+      artifact_kind: "container",
+      artifact_format: "directory",
+    });
+    expect(
+      edges.find(
+        ({ occurrence_id }) => occurrence_id === directory.occurrence_id,
+      ),
+    ).toMatchObject({
+      relation: "contains",
+      parent_artifact_id: contentId("1"),
+    });
+    expect(limitations).toEqual([]);
+  });
 });
 
 const fat = (wide = false): Buffer =>

src/artifacts/inventory/ArtifactGraphConstruction.ts

@@ -295,7 +295,9 @@ export const createArtifactEdges = (
   const edges: ArtifactEdge[] = [];
   const limitations: string[] = [];
   for (const occurrence of occurrences) {
-    const isSourceMap = occurrence.logical_path.toLowerCase().endsWith(".map");
+    // Use the occurrence's own classification: a directory named `x.map` is
+    // a container, not a source map of its sibling.
+    const isSourceMap = occurrence.artifact_kind === "source-map";
     const sourcePath = isSourceMap
       ? occurrence.logical_path.slice(0, -".map".length)
       : undefined;
@@ -337,8 +339,10 @@ export const createArtifactEdges = (
       relation:
         occurrence.entry_kind === "slice"
           ? ("slice-of" as const)
-          : isSourceMap && mappedSource === undefined
-            ? ("contains" as const)
+          : isSourceMap
+            ? mappedSource === undefined
+              ? ("contains" as const)
+              : ("maps-source" as const)
             : relationFor(occurrence.logical_path),
       occurrence_id: occurrence.occurrence_id,
     };
@@ -587,11 +591,8 @@ const classifyFatArtifact = (
   return identity.state === "mach-o" ? "mach-o-universal" : "unknown";
 };
 
-const relationFor = (path: string): ArtifactEdge["relation"] => {
-  const lower = path.toLowerCase();
-  if (lower.endsWith(".map")) return "maps-source";
-  if (lower.includes(".framework/")) return "embeds";
-  return "contains";
-};
+/** Relation of a non-source-map occurrence to its parent. */
+const relationFor = (path: string): ArtifactEdge["relation"] =>
+  path.toLowerCase().includes(".framework/") ? "embeds" : "contains";
 
 const depth = (path: string): number => path.split("/").length;