Add notes about how annotate/sort should be decoupled/reörganized

src/metabase/query_processor/annotate.clj

 (ns metabase.query-processor.annotate
-  "Code that analyzes the results of running a query and adds relevant type information about results (including foreign key information).
-   TODO - The code in this namespace could definitely use a little cleanup to make it a little easier to wrap one's head around :)"
+  "Code that analyzes the results of running a query and adds relevant type information about results (including foreign key information)."
+  ;; TODO - The code in this namespace could definitely use a little cleanup to make it a little easier to wrap one's head around :)
+  ;; TODO - This namespace should be called something like `metabase.query-processor.middleware.annotate`
   (:require [clojure
              [set :as set]
              [string :as str]]

src/metabase/query_processor/middleware/annotate_and_sort.clj

 (ns metabase.query-processor.middleware.annotate-and-sort
   "Middleware for annotating (adding type information to) the results of a query and sorting the columns in the results."
+  ;; TODO - `annotate` and `sort` are technically two seperate steps. We should decouple them and replace
+  ;; `metabase.query-processor.annotate`, ``metabase.query-processor.sort`, and `metabase.query-processor.middleware.annotate-and-sort`
+  ;; with two namespaces called `metabase.query-processor.middleware.annotate` and `metabase.query-processor.middleware.sort`
   (:require [metabase.driver :as driver]
-            (metabase.query-processor [annotate :as annotate]
-                                      [util :as qputil])))
+            [metabase.query-processor
+             [annotate :as annotate]
+             [util :as qputil]]))
 
 (def ^:private ^:const ^Integer max-rows-to-scan-for-column-type-inference
   "Maximum number of rows to scan to look for a non-`nil` value to determine type information.

src/metabase/query_processor/sort.clj

 (ns metabase.query-processor.sort
   "Code for determining the order columns should be returned in from query results."
+  ;; TODO - This namespace should be called something like `metabase.query-processor.middleware.sort`
   (:require [clojure.tools.logging :as log]
             [metabase.query-processor.interface :as i]
             [metabase.util :as u]))