Add support for showing scheduler_hints in server details

Nova currently lacks a straightforward way to expose scheduler hints
associated with a server. This change extends existing Nova's
API to allow users to retrieve this information when it is available.
It adds a new API microversion to support returning the associated
scheduler_hints in ``GET /servers/{server_id}``, `GET /servers/detail``,
``PUT /servers/{server_id}`` and ``POST /server/{server_id}/action``
(rebuild) responses.

Implements: blueprint show-scheduler-hints-in-server-details
Change-Id: If0070cfbc218e0515bf3b58fc8c5067ae22c7072

api-ref/source/servers.inc

@@ -671,6 +671,7 @@ Response
   - fault.details: fault_details
   - pinned_availability_zone: pinned_availability_zone
   - progress: progress
+  - scheduler_hints: scheduler_hints
   - security_groups: security_groups_obj_optional
   - security_group.name: name
   - servers_links: servers_links
@@ -681,6 +682,11 @@ Response
   - trusted_image_certificates: server_trusted_image_certificates_resp
   - locked_reason: locked_reason_resp
 
+**Example List Servers Detailed (2.100)**
+
+.. literalinclude:: /../../doc/api_samples/servers/v2.100/servers-details-resp.json
+   :language: javascript
+
 **Example List Servers Detailed (2.98)**
 
 .. literalinclude:: /../../doc/api_samples/servers/v2.98/servers-details-resp.json
@@ -806,6 +812,7 @@ Response
   - fault.details: fault_details
   - pinned_availability_zone: pinned_availability_zone
   - progress: progress
+  - scheduler_hints: scheduler_hints
   - security_groups: security_groups_obj_optional
   - security_group.name: name
   - locked: locked
@@ -816,6 +823,11 @@ Response
   - server_groups: server_groups_2_71
   - locked_reason: locked_reason_resp
 
+**Example Show Server Details (2.100)**
+
+.. literalinclude:: ../../doc/api_samples/servers/v2.100/server-get-resp.json
+   :language: javascript
+
 **Example Show Server Details (2.98)**
 
 .. literalinclude:: ../../doc/api_samples/servers/v2.98/server-get-resp.json