Fixed Vulnerabilities reported by Wordfence

• Security Fix: Stored XSS via frontend property submission (added nonce and capability checks, sanitized property meta, escaped price text output)
• Security Fix: Users could overwrite posts they do not own through the frontend property form
• Security Fix: Stored XSS via agent registration fields (registration data is now sanitized and escaped on the Agents admin page)
• Security Fix: reCAPTCHA could be bypassed on agent registration, login and contact forms by omitting the captcha response
• Security Fix: Agent passwords are no longer stored as plain text user meta on auto approved registrations
• New Filter: rem_user_can_submit_property to allow custom roles to submit properties from frontend