Add Oracle 26ai support and templates

[martinfanning1]

Add support for Oracle "26ai": new installation tasks, variables, and DDL template.

Introduces roles/oracle/tasks/26ai_install.yml to install the Oracle 26ai RPM and prereq package, and adds roles/oracle/vars/v23.26.1.0.0.yml to declare 26ai-specific vars (prereq URLs, base version/installer, oracle_family, sql_username).

The reason for the 2 additions to the role yaml file for 26ai [v23.26.1.0.0.yml] are as follows:

oracle_family - Added to the yaml file to ensure current code to get the oracle_family still works with earlier versions e.g. 19, 12, 11 etc…. Current code parses the oracle version to get the oracle_family i.e. oracle_family: "{{ oracle_version.split('.') | first }}c". In 26ai the version is different i.e. 23.26.1.0.0 due to the history of Oracle 26ai being renamed from 23ai and ultimately releases - however the version numbering looked to be maintained as 23.X.X.X.X

sql_username - Added to the yaml to accommodate a change in Oracle 26ai (stemming originally from Oracle 21) where the default architecture is now a multitenant architecture in Oracle. Where the DB is created as a CDB (Container Database) and any role or username created within this context must start with the C## prefix. Up to now this was not enforced and roles and users could be created without the prefix - in 26ai you do not need to use the prefix in PDB (Pluggable Databases) which are in effect the tenants of the CDB in this multitenant architecture. For initial install and testing we choose to use the CB to deploy the Curam Schema (and tables)

Update roles/oracle/tasks/configure.yml to branch database creation for oracle_family=="26ai" (dbca invocation and conditional), and to select the appropriate CuramPostInstall DDL template. Remove params in Create Database for EM Express

In 26ai the Oracle Enterprise Manager Database Express (EM Express) has been desupported. Up to now we have created an Oracle database with this feature (using specific flags in the create database command), although from research it was not really used. So the command to create an Oracle database needed to be changed for 26ai - and we have separated this out based on the oracle_family version specified.

Fix CuramPostInstall.ddl.j2 to use @ for script invocation and add a new CuramPostInstall26ai.ddl.j2 with 26ai-specific role/user/grants and system settings - To accommodate new CBD Architecture in 26ai

Added in a fix to the CuramPostInstall script to correctly call the xaview configuration sql file for non. 26ai installs
New file added for a custom CuramPostInstall file for Oracle 26ai due to the changes required for now enforced multitenant architecture i.e. adding in the prefix C## as outlined above.

[martinfanning1]

@ourboy All valid checks have now passed - I don't know why it expects the 2 pending checks..
They are no longer in the molecule tests - but they need to be bypassed...