Clarify storage limits and unify file metadata displays

apps/server/drizzle/0013_file_upload_contexts.sql

@@ -0,0 +1,8 @@
+CREATE TABLE `file_upload_contexts` (
+  `fileId` text PRIMARY KEY NOT NULL,
+  `context` text NOT NULL,
+  `expiresAt` integer NOT NULL,
+  FOREIGN KEY (`fileId`) REFERENCES `files`(`id`) ON DELETE CASCADE
+);
+--> statement-breakpoint
+CREATE INDEX `file_upload_context_expiry` ON `file_upload_contexts` (`expiresAt`);