Persist rows-per-page preferences per user

[Tim020]

Summary

• Adds a table_page_sizes JSON column to UserSettings (Alembic migration included) so each user's per-table pagination preference is stored server-side
• Preferences follow users across devices — important for team members who use laptops during rehearsals before moving to their fixed station
• Both the Vue 3 (usePagination composable + Pinia store) and Vue 2 (paginationMixin + Vuex) clients are wired up across all ~20 paginated tables
• Updates sync via the existing WS GET_USER_SETTINGS broadcast on PATCH — no local state mutations, all sessions stay consistent

How it works

1. On component mount, reads the stored perPage value from userSettings.table_page_sizes[tableKey] (falls back to default 15)
2. On change, fires PATCH /api/v1/user/settings with the merged table_page_sizes object
3. Backend saves and broadcasts GET_USER_SETTINGS WS event to all sessions for that user
4. All open sessions re-fetch settings — preference is now live everywhere

Test plan

• Log in, navigate to a paginated table (e.g. Acts), change rows-per-page to 25
• Hard-refresh — table should still show 25 rows per page
• Log in on a second browser/device — same preference applies
• Verify GET /api/v1/user/settings returns table_page_sizes: {"config_acts": 25}
• Change per-page on a second table — confirm the two tables store independent values
• Log out and back in — preferences persist across sessions

🤖 Generated with Claude Code

[github-actions]

Client V3 Test Results

23 tests   23 ✅  0s ⏱️
 2 suites   0 💤
 1 files     0 ❌

Results for commit 32afb49.

[github-actions]

Playwright E2E Results (chromium)

175 tests   175 ✅  1m 54s ⏱️
 14 suites    0 💤
  1 files      0 ❌

Results for commit 32afb49.

♻️ This comment has been updated with latest results.

[github-actions]

Client Test Results

128 tests   128 ✅  0s ⏱️
  6 suites    0 💤
  1 files      0 ❌

Results for commit 32afb49.

[sonarqubecloud]

Quality Gate passed

Issues
3 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Python Test Results

  1 files    1 suites   2m 2s ⏱️
662 tests 662 ✅ 0 💤 0 ❌
667 runs  667 ✅ 0 💤 0 ❌

Results for commit 32afb49.

[github-actions]

Playwright E2E Results (firefox)

175 tests   175 ✅  1m 53s ⏱️
 14 suites    0 💤
  1 files      0 ❌

Results for commit 32afb49.