kdesc --typeface from the reflection klammerset; a missing font directory is a row, not an error

Assembled from klammertext-dev daad6273483a. The font-store listing is
rendered from ref/ (one table per search directory, in search order,
with the styles each typeface holds); the search path is described,
not validated, so a KLAMMERTEXT_FONTS directory that does not exist --
the default ~/.klammertext/fonts on a fresh install -- is a row saying
so and the command exits 0. A typeface an earlier directory also holds
is marked shadowed, with the winning directory, in a column present only
when needed. The store's layout convention has one reader,
fonts_in_directory(). Six kdesc suite cases pin the listing.

mac/font_store.h

@@ -28,6 +28,13 @@ std::vector<std::string> installed_font_dirs();
 std::string default_font_dir();
 // Every installable font family found across those directories.
 std::vector<std::string> available_font_families();
+// Every font ONE base directory holds, in directory-name order: each
+// <name>.css beside a <name>/ directory, the family name read from the css
+// (the directory name when the css declares none), the styles classified.
+// Empty for a directory that does not exist or holds no fonts; the caller
+// asks the filesystem which.  The store's layout convention lives here, so
+// a listing of the store (kdesc --typeface) reads it rather than restating it.
+std::vector<Resolved_font> fonts_in_directory(const std::string& base);
 // Whether the store can resolve NAME -- written as the family name or as
 // the store's directory name, since both resolve.  The question a klammer
 // asks before it names a typeface that is not shipped (a CJK face), so it
@@ -61,9 +68,6 @@ std::vector<Font_file> classify_font_files(const std::string& directory);
 // generated <family-kebab>.css with relative urls.  Returns a report.
 std::string install_fonts(const std::string& source_dir, std::string dest_dir = "");
 
-// Describe every font in the store with provenance and variants.
-std::string describe_fonts();
-
 // Write an HTML specimen page for fonts into output_dir.  With an empty
 // source_dir, samples every available font in the store; otherwise
 // classifies and samples the (possibly uninstalled) fonts in source_dir.