feat: add sharing info to /workspaces endpoint (#21049)

closes: https://github.com/coder/internal/issues/858

Similar to https://github.com/coder/coder/pull/19375, this one uses
system permissions for fetching actual user and group data.

Modifies the `workspaces_expanded` view to fetch the required data; this way it's made available to all code paths that make use of it.  

Also fixes a bug in a test helper function that can result in `null` being saved to the DB for `user_acl` or `group_acl` and break tests; a defensive check constraint that prevents this is worth a PR, e.g:

`ALTER TABLE workspaces
   ADD CONSTRAINT group_acl_is_object CHECK (jsonb_typeof(group_acl) = 'object');`

Also adds missing  `OwnerName` in `ConvertWorkspaceRows`.

coderd/database/sqlc.yaml

@@ -91,6 +91,12 @@ sql:
           - column: "workspaces_expanded.group_acl"
             go_type:
               type: "WorkspaceACL"
+          - column: "workspaces_expanded.user_acl_display_info"
+            go_type:
+              type: "WorkspaceACLDisplayInfo"
+          - column: "workspaces_expanded.group_acl_display_info"
+            go_type:
+              type: "WorkspaceACLDisplayInfo"
           - column: "notification_templates.actions"
             go_type:
               type: "[]byte"
@@ -159,6 +165,8 @@ sql:
           jwt: JWT
           user_acl: UserACL
           group_acl: GroupACL
+          user_acl_display_info: UserACLDisplayInfo
+          group_acl_display_info: GroupACLDisplayInfo
           troubleshooting_url: TroubleshootingURL
           default_ttl: DefaultTTL
           motd_file: MOTDFile