Add dueDate to reminders, remove reminder from notes

Schema changes:
- Added dueDate field to companyReminders table
- Removed reminderDate and reminderSent from notes table

Backend changes:
- Updated company-reminder.service with dueDate handling
- Added getUpcomingReminders function for dashboard
- Simplified note.service (removed reminder logic)
- Updated validators and routes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/db/schema.js

@@ -132,11 +132,12 @@ export const projects = pgTable('projects', {
   updatedAt: timestamp('updated_at').defaultNow().notNull(),
 });
 
-// Company reminders table - jednoduché pripomienky naviazané na firmu
+// Company reminders table - pripomienky naviazané na firmu s dátumom
 export const companyReminders = pgTable('company_remind', {
   id: uuid('id').primaryKey().defaultRandom(),
   companyId: uuid('company_id').references(() => companies.id, { onDelete: 'cascade' }).notNull(),
   description: text('description').notNull(),
+  dueDate: timestamp('due_date'), // kedy má byť splnená
   isChecked: boolean('is_checked').default(false).notNull(),
   createdAt: timestamp('created_at').defaultNow().notNull(),
   updatedAt: timestamp('updated_at').defaultNow().notNull(),
@@ -181,7 +182,7 @@ export const todoUsers = pgTable('todo_users', {
   todoUserUnique: unique('todo_user_unique').on(table.todoId, table.userId),
 }));
 
-// Notes table - poznámky
+// Notes table - poznámky (bez reminder funkcionalít)
 export const notes = pgTable('notes', {
   id: uuid('id').primaryKey().defaultRandom(),
   title: text('title'),
@@ -190,8 +191,6 @@ export const notes = pgTable('notes', {
   projectId: uuid('project_id').references(() => projects.id, { onDelete: 'cascade' }), // alebo projektu
   todoId: uuid('todo_id').references(() => todos.id, { onDelete: 'cascade' }), // alebo todo
   contactId: uuid('contact_id').references(() => contacts.id, { onDelete: 'cascade' }), // alebo kontaktu
-  reminderDate: timestamp('reminder_date'), // dátum a čas pre reminder
-  reminderSent: boolean('reminder_sent').default(false).notNull(), // či už bol reminder odoslaný
   createdBy: uuid('created_by').references(() => users.id, { onDelete: 'set null' }),
   createdAt: timestamp('created_at').defaultNow().notNull(),
   updatedAt: timestamp('updated_at').defaultNow().notNull(),