feat(freeradius): enable sqlippool for centralized IP allocation

- Add sqlippool module configuration
- Integrate sqlippool into authorize, post-auth, and accounting sections
- Add radippool table schema (InnoDB)
- Update Helm ConfigMap and Deployment templates
- Enable centralized IP management for OpenVPN cluster
- Bump Helm chart version to 1.0.12

files/sites-available/default

@@ -619,7 +619,7 @@ accounting {
 
 	#  Return an address to the IP Pool when we see a stop record.
 	#  Ensure that &control:Pool-Name is set to determine which pool of IPs are used.
-#	sqlippool
+	sqlippool
 
 	#  Log traffic to an SQL database.
 	#  See "Accounting queries" in mods-available/sql
@@ -752,7 +752,7 @@ post-auth {
 	#
 	#  Ensure that &control:Pool-Name is set to determine which
 	#  pool of IPs are used.
-#	sqlippool
+	sqlippool
 
 
 	#  Create the CUI value and add the attribute to Access-Accept.