Fix week numbering being off by one and add custom semester starts per module

app/models/lecture.rb

@@ -13,7 +13,7 @@ class Lecture < ApplicationRecord
   ], default: :undetermined
 
   def week_number
-    ((start_time.beginning_of_week - START_OF_YEAR_5_SEMESTER_1) / 1.week).floor
+    ((start_time.beginning_of_week - course.semester_start_date.to_time) / 1.week).floor + 1
   end
 
   def live_video_url

db/migrate/20231001165128_add_semester_start_date_to_course.rb

@@ -0,0 +1,5 @@
+class AddSemesterStartDateToCourse < ActiveRecord::Migration[7.0]
+  def change
+    add_column :courses, :semester_start_date, :date, default: START_OF_YEAR_5_SEMESTER_1.to_date
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2023_10_01_163055) do
+ActiveRecord::Schema[7.0].define(version: 2023_10_01_165128) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -30,6 +30,7 @@ ActiveRecord::Schema[7.0].define(version: 2023_10_01_163055) do
     t.jsonb "panopto_folders"
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
+    t.date "semester_start_date", default: "2023-10-02"
   end
 
   create_table "lectures", force: :cascade do |t|