feat: add count endpoint for users, enabling better pagination (#4848)

* Start on backend

* Hook up frontend

* Add to frontend test

* Add go test, wip

* Fix some test bugs

* Fix test

* Format

* Add to authorize.go

* copy user array into local variable

* Authorize route

* Log count error

* Authorize better

* Tweaks to authorization

* More authorization tweaks

* Make gen

* Fix test

Co-authored-by: Garrett <garrett@coder.com>

coderd/database/queries/users.sql

@@ -39,6 +39,41 @@ FROM
 WHERE
     status = 'active'::user_status AND deleted = false;
 
+-- name: GetFilteredUserCount :one
+SELECT
+	COUNT(*)
+FROM
+	users
+WHERE
+	users.deleted = @deleted
+	-- Start filters
+	-- Filter by name, email or username
+	AND CASE
+		WHEN @search :: text != '' THEN (
+			email ILIKE concat('%', @search, '%')
+			OR username ILIKE concat('%', @search, '%')
+		)
+		ELSE true
+	END
+	-- Filter by status
+	AND CASE
+		-- @status needs to be a text because it can be empty, If it was
+		-- user_status enum, it would not.
+		WHEN cardinality(@status :: user_status[]) > 0 THEN
+			status = ANY(@status :: user_status[])
+		ELSE true
+	END
+	-- Filter by rbac_roles
+	AND CASE
+		-- @rbac_role allows filtering by rbac roles. If 'member' is included, show everyone, as everyone is a member.
+		WHEN cardinality(@rbac_role :: text[]) > 0 AND 'member' != ANY(@rbac_role :: text[])
+		THEN rbac_roles && @rbac_role :: text[]
+		ELSE true
+	END
+	-- Authorize Filter clause will be injected below in GetAuthorizedUserCount
+	-- @authorize_filter
+;
+
 -- name: InsertUser :one
 INSERT INTO
 	users (