feat: User pagination using offsets (#1062)

Offset pagination and cursor pagination supported

coderd/database/queries/users.sql

@@ -56,4 +56,42 @@ WHERE
 SELECT
 	*
 FROM
-	users;
+	users
+WHERE
+	CASE
+		-- This allows using the last element on a page as effectively a cursor.
+		-- This is an important option for scripts that need to paginate without
+		-- duplicating or missing data.
+		WHEN @after_user :: uuid != '00000000-00000000-00000000-00000000' THEN (
+		    	-- The pagination cursor is the last user of the previous page.
+		    	-- The query is ordered by the created_at field, so select all
+		    	-- users after the cursor. We also want to include any users
+		    	-- that share the created_at (super rare).
+				created_at >= (
+					SELECT
+						created_at
+					FROM
+						users
+					WHERE
+						id = @after_user
+				)
+				-- Omit the cursor from the final.
+				AND id != @after_user
+			)
+			ELSE true
+	END
+	AND CASE
+		WHEN @search :: text != '' THEN (
+			email LIKE concat('%', @search, '%')
+			OR username LIKE concat('%', @search, '%')
+			OR 'name' LIKE concat('%', @search, '%')
+		)
+		ELSE true
+	END
+ORDER BY
+    -- Deterministic and consistent ordering of all users, even if they share
+    -- a timestamp. This is to ensure consistent pagination.
+	(created_at, id) ASC OFFSET @offset_opt
+LIMIT
+	-- A null limit means "no limit", so -1 means return all
+	NULLIF(@limit_opt :: int, -1);