[resource-manager]: Make default LRO Options for RPaaS services more explicit

Add documentation, samples, and perhaps operation aliases for preferred LRO Options for RPaaS operations.

Currently, the default templates are using some older patterns (like location header), and we should
(1) Have clear documentation on which templates to use
(2) Have an RPaaS LRO sample that demonstrates appropriate usage
(3) Consider template aliases for RPaaS LROs that use RPaaS recommended options

Start by locating the default LRO templates and any existing RPaaS samples in the repository, then compare their options with the recommended RPaaS patterns described in the issue. Done means the preferred templates are documented, an RPaaS LRO sample demonstrates the usage, and any agreed operation aliases are included; the issue leaves the exact files and alias scope to determine.

Written by the indexing model from the issue text.