- Descriptions now render Markdown or sanitized HTML via [includes/db.php](/Users/tyemeclifford/Documents/GH/mediaplayer/includes/db.php).

Public player descriptions render formatted HTML on the homepage.
Catalogue cards, embed meta tags, and social metadata use safe 
plain-text excerpts.
Add/edit admin pages now use a rich description editor that preserves 
pasted HTML styling, with a textarea fallback for no-JS.
External/YouTube-imported descriptions are sanitized before storage.
README now documents Markdown/HTML description support.

cli/admin.php

@@ -27,6 +27,10 @@ function cli_main(array $argv): int {
         $command = 'help';
     }
 
+    if (cli_command_requires_database_write($command)) {
+        cli_assert_database_writable();
+    }
+
     return match ($command) {
         'help' => cli_help(),
         'site:status', 'status' => cli_site_status(),
@@ -51,6 +55,7 @@ function cli_main(array $argv): int {
         'maintenance:external-views' => cli_maintenance_external_views($parsed),
         'maintenance:all' => cli_maintenance_all($parsed),
         'db:path' => cli_db_path(),
+        'db:doctor' => cli_db_doctor(),
         'db:backup' => cli_db_backup($parsed),
         'db:vacuum' => cli_db_vacuum(),
         default => cli_unknown($command),
@@ -157,6 +162,7 @@ Maintenance:
 
 Database:
   db:path
+  db:doctor
   db:backup [--output=/path/to/media.db]
   db:vacuum
 
@@ -164,6 +170,46 @@ HELP;
     return 0;
 }
 
+function cli_command_requires_database_write(string $command): bool {
+    return in_array($command, [
+        'settings:set',
+        'admin:password',
+        'password:set',
+        'video:add',
+        'video:update',
+        'video:publish',
+        'video:unpublish',
+        'video:toggle',
+        'video:delete',
+        'source:add',
+        'source:update',
+        'source:delete',
+        'maintenance:catalogue-order',
+        'maintenance:youtube-timestamps',
+        'maintenance:external-views',
+        'maintenance:all',
+        'db:vacuum',
+    ], true);
+}
+
+function cli_assert_database_writable(): void {
+    $paths = cli_database_writable_checks();
+    $problems = [];
+
+    foreach ($paths as $check) {
+        if (!$check['ok']) $problems[] = $check['message'];
+    }
+
+    if ($problems) {
+        $details = implode(PHP_EOL . '  - ', $problems);
+        throw new RuntimeException(
+            "Database is not writable by the current CLI user (" . cli_current_user_label() . ")." .
+            PHP_EOL . "  - " . $details .
+            PHP_EOL . "Run db:doctor for details, then make the data directory and media.db writable by this user."
+        );
+    }
+}
+
 function cli_unknown(string $command): int {
     fwrite(STDERR, "Unknown command: {$command}" . PHP_EOL . PHP_EOL);
     cli_help();
@@ -768,6 +814,66 @@ function cli_db_path(): int {
     return 0;
 }
 
+function cli_db_doctor(): int {
+    $rows = [
+        ['Current user', cli_current_user_label()],
+        ['Database path', DB_PATH],
+        ['Data directory', dirname(DB_PATH)],
+        ['Database exists', cli_yes_no(file_exists(DB_PATH))],
+    ];
+
+    foreach (cli_database_writable_checks() as $check) {
+        $rows[] = [$check['label'], $check['ok'] ? 'ok' : $check['message']];
+    }
+
+    cli_table(['check', 'result'], $rows);
+    return 0;
+}
+
+function cli_database_writable_checks(): array {
+    $directory = dirname(DB_PATH);
+    $checks = [];
+
+    $checks[] = [
+        'label' => 'data directory',
+        'ok' => is_dir($directory) && is_writable($directory),
+        'message' => is_dir($directory)
+            ? "data directory is not writable: {$directory}"
+            : "data directory does not exist: {$directory}",
+    ];
+
+    if (file_exists(DB_PATH)) {
+        $checks[] = [
+            'label' => 'media.db',
+            'ok' => is_writable(DB_PATH),
+            'message' => "database file is not writable: " . DB_PATH,
+        ];
+    }
+
+    foreach ([DB_PATH . '-wal', DB_PATH . '-shm'] as $path) {
+        if (!file_exists($path)) continue;
+        $checks[] = [
+            'label' => basename($path),
+            'ok' => is_writable($path),
+            'message' => "SQLite sidecar file is not writable: {$path}",
+        ];
+    }
+
+    return $checks;
+}
+
+function cli_current_user_label(): string {
+    if (function_exists('posix_geteuid') && function_exists('posix_getpwuid')) {
+        $uid = posix_geteuid();
+        $info = posix_getpwuid($uid);
+        $name = is_array($info) && isset($info['name']) ? (string)$info['name'] : '';
+        return $name !== '' ? "{$name} (uid {$uid})" : "uid {$uid}";
+    }
+
+    $user = get_current_user();
+    return $user !== '' ? $user : 'unknown';
+}
+
 function cli_db_backup(array $parsed): int {
     cli_db()->exec('PRAGMA wal_checkpoint(FULL)');