fix(database): keep single-attribute indexes under MariaDB 768-byte limit

- hostname column 1024 -> 255. DNS hostnames are capped at 253 chars, so
  the wider size never gained anything but pushed the bloom_filter index
  past the InnoDB/utopia-php-database 768-byte single-attribute index
  prefix limit.
- path column stays at 1024 for data fidelity (URLs with signed query
  strings exceed 255), but its index entry now uses an explicit
  lengths=[255] so MariaDB only indexes the first 255 chars. The index
  validator in utopia/database treats lengths[i] as the indexLength when
  set, taking the column under the 768 cap while preserving the full
  column for stored data.

Caught by CI when the full Database adapter suite ran against MariaDB —
local runs skipped 45 DatabaseTest cases because pdo_mysql wasn't loaded.
Verified locally now via docker-compose: 195/195 passing.

Author: lohanidamodar

src/Usage/Metric.php

@@ -617,7 +617,7 @@ public static function getEventSchema(): array
             $stringColumn('teamInternalId', 255),
             $stringColumn('country', 2),
             $stringColumn('region', 64),
-            $stringColumn('hostname', 1024),
+            $stringColumn('hostname', 255),
             $stringColumn('osCode', 256),
             $stringColumn('osName', 256),
             $stringColumn('osVersion', 255),
@@ -721,11 +721,20 @@ public static function getEventIndexes(): array
         ];
 
         return array_map(
-            static fn (string $col): array => [
-                '$id' => 'index-' . $col,
-                'type' => 'key',
-                'attributes' => [$col],
-            ],
+            static function (string $col): array {
+                $entry = [
+                    '$id' => 'index-' . $col,
+                    'type' => 'key',
+                    'attributes' => [$col],
+                ];
+                // path is sized 1024 for data fidelity; cap the index key at
+                // 255 so the MariaDB single-attribute index stays within the
+                // 768-byte InnoDB key prefix limit.
+                if ($col === 'path') {
+                    $entry['lengths'] = [255];
+                }
+                return $entry;
+            },
             $indexed,
         );
     }