Aug 7 - Update new design as default

CLAUDE.md

@@ -166,6 +166,7 @@ part of the tree — see §7. Device registration on the API side lives in
 | `GROQ_MODEL` | Optional. Groq model ID. Defaults to `llama-3.3-70b-versatile`. |
 | `ENROLLMENT_NOTIFY_EMAILS` | Optional. Comma-separated extra addresses alerted on a new enrollment, **in addition to** every active `admin` account. For people who should be told but hold no JQC login. |
 | `ENROLLMENT_DIR` | Optional. Directory for enrollment-form JSON submissions. Defaults to `<instance_path>/enrollments` (git-ignored). Created at boot. |
+| `DEFAULT_UI_THEME` | Optional, default `modern` (phase50). The design shown when a user has no stored preference — i.e. new accounts and unauthenticated pages. A stored `users.ui_theme` always wins. Set `classic` to revert the default **without** touching anyone's saved choice. |
 | `COMMENTS_VISIBLE_TO_ALL` | Optional, default `true`. **TEMPORARY (Aug 2026).** When true, customers see *every* comment on an issue, not only those ticked "Share with customer". Set `false` to restore the phase22 staff-only filtering — `is_customer_visible` is still written on every comment, so the revert needs no data repair. |
 | `PHOTO_STAMP_ENABLED` | Optional, default `true`. Burns a capture-time + geo overlay into photos uploaded via `POST /api/v1/photos/upload`. Set `false` to store raw uploads. |
 
@@ -908,7 +909,22 @@ phase1_projects_roles → phase6_features → phase7_mobile_api → phase8_notif
                                                                                             → phase46_followup_req_by
                                                 → phase47_sched_acknowledged
                                                     → phase48_user_ui_theme
-                                                        → phase49_external_inspector   ← HEAD
+                                                        → phase49_external_inspector
+                                                            → phase50_default_modern   ← HEAD
+
+#### phase50 — modern design becomes the default
+
+Revision id `phase50_default_modern`. Promotes the phase48 A/B-test design to the default. Two changes, **both required**: the `users.ui_theme` column default becomes `'modern'` (new accounts), and existing rows are moved `'classic'` → `'modern'`. phase48 stored a literal `'classic'` for everyone rather than NULL, so a default change alone would leave every current user on the old design.
+
+**It overwrites a deliberate choice** — phase48 gave no way to tell "I picked classic" from "I never touched it", so anyone who actively preferred classic is moved too. They can switch back from the account menu and that choice then sticks; the switcher is unchanged. `/ui/theme-votes` reads the same column, so the tally reads 100% modern afterwards — capture it first if the numbers matter. `downgrade()` returns *everyone* to classic (individual prior choices were never recorded).
+
+To change the default without touching saved preferences, set `DEFAULT_UI_THEME=classic` instead of running this.
+
+**Deploy order:**
+```bash
+flask db upgrade
+sudo systemctl restart gunicorn
+```
 
 #### phase49 — External Inspector role