Add n8n workflow schedule type, Swedish date format, and Data & Privacy page

- New "n8n workflow" schedule type for manually tracked tasks, plumbed
  through the form, filters, group labels, and API validation, same as
  the earlier backup/update types.
- Dates (cron next-run, server last-seen) now render in Swedish
  standard format (YYYY-MM-DD, 24-hour clock) via a shared formatter
  instead of the browser's default locale.
- New Data & Privacy page describing what's stored, where, how long,
  and how to remove it, linked from a footer shown on every page
  alongside a "By bobbantech" credit linking to bobbantech.com.

server/src/db/schema.ts

@@ -20,7 +20,7 @@ export const scheduledTasks = sqliteTable("scheduled_tasks", {
   serverId: integer("server_id")
     .notNull()
     .references(() => servers.id, { onDelete: "cascade" }),
-  scheduleType: text("schedule_type").notNull(), // 'cron' | 'systemd_timer' | 'docker' | 'backup' | 'update' | 'manual'
+  scheduleType: text("schedule_type").notNull(), // 'cron' | 'systemd_timer' | 'docker' | 'backup' | 'update' | 'n8n_workflow' | 'manual'
   origin: text("origin").notNull().default("agent"), // 'agent' | 'manual' — manual rows are never touched by agent sync
   name: text("name").notNull(),
   command: text("command"),

server/src/routes/tasks.ts

@@ -58,7 +58,7 @@ tasksRouter.get("/", async (req, res) => {
 
 const manualTaskSchema = z.object({
   serverId: z.number().int(),
-  scheduleType: z.enum(["cron", "systemd_timer", "docker", "backup", "update", "manual"]),
+  scheduleType: z.enum(["cron", "systemd_timer", "docker", "backup", "update", "n8n_workflow", "manual"]),
   name: z.string().min(1).max(200),
   command: z.string().max(1000).optional(),
   scheduleExpression: z.string().max(200).optional(),