Add database object name configurability to support multiple instances and custom schemas and table names

[ArHndotAgz]

Description
This PR enhances Hangfire.Oracle.Core with full database object name configurability, allowing for multiple Hangfire instances in the same database and custom schema support.
Key Features
• Configure schema name via external configuration
• Support unique instance names to avoid conflicts
• Customize table names, sequences, and other database objects
• Run multiple Hangfire instances side-by-side in the same schema
Breaking Changes
• Configuration structure has changed to support the new naming options
• Existing implementations will need to provide configuration or adapt to new defaults
• Database migration may be required when upgrading from previous versions
Migration Guide
Users upgrading from previous versions will need to:

1. Define a configuration file with their desired naming scheme
2. Update their Hangfire initialization code to use the new configuration options
3. Potentially migrate existing data if changing names of existing installations