What is the detailed process for applying for an Indian passport online, including the specific steps involved for first-time applicants, passport renewal, and minor passport applications? What are the mandatory and optional documents required for each category? How can I schedule an appointment at a Passport Seva Kendra (PSK), and what is the procedure to follow during the appointment? Are there any specific guidelines for applicants belonging to different categories, such as government employees, senior citizens, or those residing in remote areas? Additionally, what are the common reasons for passport application rejection, and how can these be avoided?