Land feature 57's controller work on its release branch

The controller plans config, templates and moved providers' provisions,
hands bus accounts to the vault and judges the new manifest words, on the
feature's SDK and node-engine validator (feature 57, config and provisioning).

internal/builder/template_test.go

@@ -2,6 +2,8 @@ package builder
 
 import (
 	"context"
+	"crypto/sha256"
+	"encoding/hex"
 	"os"
 	"path/filepath"
 	"strings"
@@ -134,3 +136,46 @@ func writeTree(t *testing.T, dir string, files map[string]string) string {
 	}
 	return dir
 }
+
+// A module whose files/ is an archive unpacked onto the machine keeps its templates in a directory it names (issue
+// 731): the build reads each template back from the archive packed from that directory, and files/ is packed as it
+// was, its templates nowhere in it.
+const unpackingModule = `{"module":"meshboard","version":"1",
+  "templates":"templates",
+  "build":{"artifacts":[
+    {"name":"scripts","kind":"archive","from":"files"},
+    {"name":"templates","kind":"archive","from":"templates"}]},
+  "resources":[
+    {"id":"scripts","type":"archive","path":"/usr/local/lib/meshboard","artifact":"scripts"},
+    {"id":"conf","type":"file","path":"/etc/meshboard/meshboard.conf","template":"templates/meshboard.conf"}]}`
+
+func TestABuildReadsEachTemplateBackFromTheTemplatesDirectoryItsManifestNames(t *testing.T) {
+	files := map[string]string{"files/bin/meshboard-hook": "#!/bin/sh\n", "templates/meshboard.conf": "listen = 8080\n"}
+	r, workspace := aRepository(t, unpackingModule, files)
+	got, err := Build(context.Background(), r.run, r, "https://forge.invalid/meshboard.git", "", "", workspace, nil,
+		Npmrc{}, GitCredential{}, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if text := contentOf(t, got.Manifest, "conf"); text != files["templates/meshboard.conf"] {
+		t.Fatalf("the template's text is %q, not the file's", text)
+	}
+	if got.Manifest.Templates != "" {
+		t.Fatalf("the built manifest still names its templates directory: %q", got.Manifest.Templates)
+	}
+	// files/ packs exactly as it would with no templates beside it.
+	alone, err := pack(writeTree(t, t.TempDir(), map[string]string{"bin/meshboard-hook": "#!/bin/sh\n"}))
+	if err != nil {
+		t.Fatal(err)
+	}
+	sum := sha256.Sum256(alone)
+	packed := ""
+	for _, b := range got.Built {
+		if b.Name == "scripts" {
+			packed = b.Digest
+		}
+	}
+	if packed != "sha256:"+hex.EncodeToString(sum[:]) {
+		t.Fatalf("files/ packed to %q, not to what it packs to alone", packed)
+	}
+}