проектные команды и ссылки на источник

- заведён internal/source: уровни ссылаются друг на друга путём на диске
  или git-репозиторием, ревизия закрепляется хвостом #ref; клон делается
  заново и удаляется, кэша нет
- добавлены init, add, pull, list, check в проекте — манифест
  .conventions.toml, сборка копий по разу на компонент, маркер локальной
  части, READING.md рядом
- проверки формы развязаны с набором: принимают lang.Vocabulary, а язык
  копии узнаётся по строке о версии — манифеста рядом с ней нет

internal/manifest/manifest.go

@@ -27,12 +27,19 @@ const Name = "suite.toml"
 // binary, and making every suite declare what is already implied buys nothing.
 const DefaultLanguageCode = "ru"
 
-// Language is the [language] section: the version of the conventions language
-// and the two documents about it. The full description stays with the author of
-// the suite, the short one travels into the copy.
+// Language is the [language] section: the version of the conventions language,
+// the natural language its words are written in, and the two documents about
+// it. The full description stays with the author of the suite, the short one
+// travels into the copy.
+//
+// Source is where those two documents live. Empty means the suite itself, which
+// is where they lie while the specification of the language has no repository
+// of its own; once it moves out, the same key names it without anything else
+// changing — the vocabulary is picked by version and code either way.
 type Language struct {
 	Version     int    `toml:"version"`
 	Lang        string `toml:"lang"`
+	Source      string `toml:"source"`
 	Description string `toml:"description"`
 	Reading     string `toml:"reading"`
 }
@@ -87,12 +94,17 @@ func Load(root string) (*Manifest, error) {
 // Find walks up from start looking for a directory that holds a suite
 // manifest, so that `convy suite check` works from any subdirectory of a suite.
 func Find(start string) (string, error) {
+	return findUp(start, Name)
+}
+
+// findUp walks up from start looking for a directory holding the named file.
+func findUp(start, name string) (string, error) {
 	dir, err := filepath.Abs(start)
 	if err != nil {
 		return "", err
 	}
 	for {
-		if _, err := os.Stat(filepath.Join(dir, Name)); err == nil {
+		if _, err := os.Stat(filepath.Join(dir, name)); err == nil {
 			return dir, nil
 		}
 		parent := filepath.Dir(dir)