Uploads carry the name the file came with (#83)

An upload sends its file name next to the raw bytes, and the server keeps
it in a sidecar next to the content-addressed file. Both pickers caption
every tile and row with it, and an asset made there is named after the
file instead of "Texture" / "Font". Last upload of the same content wins.

The API's own set_error_handler ignores error_reporting(), so @-silenced
warnings still throw: a missing sidecar took the whole listing down with a
500. Existence is checked instead of suppressed.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

api/lib/FontStore.php

@@ -46,10 +46,13 @@ final class FontStore
      * libmagic versions (`font/sfnt`, `application/vnd.ms-opentype`, plain `application/octet-stream`),
      * so a second opinion from it would reject valid files rather than catch bad ones.
      *
-     * @return array{file:string,bytes:int}
+     * `$originalName` is kept beside the file as a caption (see OriginalName): the hash says
+     * nothing, and the name inside the font is deliberately never read (see `gm-font-` families).
+     *
+     * @return array{file:string,name:string,bytes:int}
      * @throws InvalidFontException when the bytes are not a supported font
      */
-    public function store(string $bytes): array
+    public function store(string $bytes, string $originalName = ''): array
     {
         $extension = self::SIGNATURES[substr($bytes, 0, 4)] ?? '';
         if ($extension === '') {
@@ -65,26 +68,29 @@ final class FontStore
         if (!is_file($path)) {
             $this->writeFile($path, $bytes);
         }
+        OriginalName::write($this->dir, $file, $originalName);
 
-        return ['file' => $file, 'bytes' => strlen($bytes)];
+        return ['file' => $file, 'name' => OriginalName::read($this->dir, $file), 'bytes' => strlen($bytes)];
     }
 
     /**
      * Every stored file, newest first – what the font picker offers. Unlike an image there is
      * nothing to read out of the header here: the picker shows each face by rendering with it.
      *
-     * @return list<array{file:string,bytes:int,updatedAt:string}>
+     * @return list<array{file:string,name:string,bytes:int,updatedAt:string}>
      */
     public function list(): array
     {
         $items = [];
         foreach (glob($this->dir . '/*.*') ?: [] as $path) {
             $file = basename($path);
+            // Sidecars share the directory and are skipped: `{hash}.ttf.json` is not a valid name.
             if (!self::isValidName($file)) {
                 continue;
             }
             $items[] = [
                 'file' => $file,
+                'name' => OriginalName::read($this->dir, $file),
                 'bytes' => (int) filesize($path),
                 'updatedAt' => gmdate('c', (int) filemtime($path)),
             ];
@@ -99,7 +105,11 @@ final class FontStore
             return false;
         }
         $path = $this->dir . '/' . $file;
-        return is_file($path) && unlink($path);
+        if (!is_file($path) || !unlink($path)) {
+            return false;
+        }
+        OriginalName::delete($this->dir, $file);
+        return true;
     }
 
     /** Temp file plus rename, so a reader never sees a half-written font (see TextureStore). */