- Use patient_master directly in list_med_inv and list_med_orginv methods
- patient_master_exten exists but lacks p_fname, p_rname, p_code fields
- Fixes blank Name/Age/Gender/P Code in /Medical/list_med_inv page
- Consistent with earlier fix for list_org_ipd
- Use patient_master table directly instead of patient_master_exten
- patient_master_exten may exist but lacks p_fname, p_rname fields
- Matches pattern used in IpdBillingModel::baseIpdListQuery()
- Fixes blank patient names/codes in /Medical/list_org_ipd page
- Update isIpdDischargedInvoice to check ONLY ipd_status field (remove fallback checks)
- Add IPD status toggle UI in discharge panel (Active/Discharged control)
- Create toggleIpdStatus controller method with permission check
- Add billing.ipd.status.manage permission for controlling bill edit lock
- Allows editing bills when needed by toggling status independently of discharge_date
- Auto-releases bed when setting status to discharged
