fix(snippets): always descend into the entrypoint root

skipDirNames prunes well-known noise (node_modules, dist, build, …) under
each entrypoint, but filepath.WalkDir invokes the callback for the root
itself first. If a consumer pointed `--entrypoint=./build` at a project
that emits TSX there, the root's basename matched the skip-list and the
walk silently produced zero files. Guard the skip check so it only fires
beneath the root, and add a regression test.

Author: kinyoklion

snippets/internal/adapters/ldapplication/ldapplication.go

@@ -109,8 +109,16 @@ func discoverFilesUnder(entrypoints []string) ([]string, error) {
 				return walkErr
 			}
 			if d.IsDir() {
-				if _, skip := skipDirNames[d.Name()]; skip {
-					return filepath.SkipDir
+				// Always descend into the entrypoint root, even if its
+				// basename happens to be in skipDirNames (e.g.
+				// `--entrypoint=./build` for a project that lays its
+				// generated TSX out there). The skip-list is meant to prune
+				// well-known noise *under* the root, not to silently turn
+				// the entire walk into a no-op.
+				if p != abs {
+					if _, skip := skipDirNames[d.Name()]; skip {
+						return filepath.SkipDir
+					}
 				}
 				return nil
 			}

snippets/internal/adapters/ldapplication/ldapplication_test.go

@@ -80,6 +80,25 @@ func TestDiscoverFilesUnder_DedupsOverlappingEntrypoints(t *testing.T) {
 	}
 }
 
+// The skip-list (node_modules, build, dist, …) prunes noise *under* the
+// entrypoint root. If the user passes one of those names *as* the
+// entrypoint (e.g. a project that emits its TSX into ./build), the walk
+// must still descend — otherwise discovery silently produces zero files.
+func TestDiscoverFilesUnder_RootMatchingSkipNameStillDescends(t *testing.T) {
+	tmp := t.TempDir()
+	root := filepath.Join(tmp, "build")
+	writeAppFile(t, root, "marker.tsx",
+		"// SDK_SNIPPET:RENDER:x/cmd hash=0 version=0.1.0\n<Snippet>x</Snippet>\n")
+
+	files, err := discoverFilesUnder([]string{root})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(files) != 1 || filepath.Base(files[0]) != "marker.tsx" {
+		t.Fatalf("expected marker.tsx under skip-named root, got %v", files)
+	}
+}
+
 // A non-directory entrypoint is rejected loudly rather than silently no-op'd.
 func TestDiscoverFilesUnder_RejectsNonDirectory(t *testing.T) {
 	tmp := t.TempDir()