FIX: Properly fix ai_summaries table sequence (#727)

* FIX: Properly fix ai_summaries table sequence

Previous attempt at 3815360 could fail due to a race introduced in 1b0ba91 where summaries are migrated to core in a post_migrate erroneously.

db/migrate/20240726164937_fix_ai_summaries_sequence.rb

@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+class FixAiSummariesSequence < ActiveRecord::Migration[7.0]
+  def up
+    begin
+      execute <<-SQL
+        SELECT
+          SETVAL (
+            'ai_summaries_id_seq',
+            (
+              SELECT
+                GREATEST (
+                  (
+                    SELECT
+                      MAX(id)
+                    FROM
+                      summary_sections
+                  ),
+                  (
+                    SELECT
+                      MAX(id)
+                    FROM
+                      ai_summaries
+                  )
+                )
+            ),
+            true
+          );
+      SQL
+    rescue ActiveRecord::StatementInvalid => e
+      # if the summary_table does not exist, we can ignore the error
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end