feat: Add dueDate (date+time) to notes and update reminders to datetime

- Add dueDate timestamp field to notes schema
- Update note validators to accept dueDate
- Update note service to handle dueDate in CRUD operations
- Fix company and project controllers to pass dueDate
- Fix route validations to include dueDate field

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/routes/company.routes.js

@@ -83,6 +83,7 @@ router.post(
   validateParams(z.object({ companyId: z.string().uuid() })),
   validateBody(z.object({
     content: z.string().min(1),
+    dueDate: z.string().optional().or(z.literal('')),
   })),
   companyController.addCompanyNote
 );
@@ -96,6 +97,7 @@ router.patch(
   })),
   validateBody(z.object({
     content: z.string().min(1).optional(),
+    dueDate: z.string().optional().or(z.literal('').or(z.null())),
   })),
   companyController.updateCompanyNote
 );