Phase 5: reporting, exports, pronouns, and roster freshness

Instructor participation report: per-student histograms, outcome mix
by class day, and a sortable table including the fairness ratio
(answered calls over questions present for, with opt-out days out of
the denominator), plus CSV exports of students, calls, and opt-outs.

Assessment scales are now per-course data: ordered levels with labels
and points out of 100 (defaults carry the old R grading values), with
calls referencing levels by id so renames follow through to history.
Renaming, re-pointing, reordering, and adding levels are always
allowed; deleting a level in use by recorded calls is blocked.

Pronouns and course term dates come from Canvas custom variable
substitutions, at launch and roster-wide via rlid-scoped NRPS; the
student page notes that names/pronouns are Canvas-sourced. Rosters
can also be refreshed outside launches: a "Sync roster now" button
and a sync-rosters CLI command for an hourly cron job, skipping ended
courses. Alembic now runs SQLite-compatible batch migrations with a
constraint naming convention.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

README.md

@@ -83,7 +83,37 @@ openssl rsa -in instance/private.key -pubout -out instance/public.key
 
 On each instructor launch the tool refreshes the course roster from
 Canvas through the Names and Role Provisioning Service, so enrollment
-changes appear without any manual step.
+changes appear without any manual step. There is also a "Sync roster
+now" button on the instructor page, and a management command suitable
+for an hourly cron job on the server, which keeps rosters current even
+when nobody has launched the tool (worth having during the add/drop
+churn at the start of a term):
+
+```
+17 * * * * cd /path/to/coldcall_lti && .venv/bin/flask --app coldcall_lti sync-rosters
+```
+
+Courses whose Canvas end date has passed are skipped automatically.
+
+Student names come from Canvas display names, which already reflect
+preferred names. Pronouns require one extra piece of Developer Key
+configuration: add a custom parameter
+
+```
+pronouns=$com.instructure.Person.pronouns
+course_start=$Canvas.course.startAt
+course_end=$Canvas.course.endAt
+```
+
+The course dates bound the schedule and date pickers; the tool works
+fine without them when a course has no dates set in Canvas.
+
+to the key. Canvas then includes each person's pronouns in launches
+and in the roster data (the tool requests memberships scoped to the
+resource link, which is what makes Canvas attach per-member custom
+fields). Pronouns appear on the live call card, printed call lists,
+and each student's own page. If the account has pronouns disabled,
+everything simply shows without them.
 
 ## Developing without Canvas