Fix ticket assignee widget incorrectly showing user after topic change

[Copilot]

Problem

When changing a ticket's topic, the assignee widget would unexpectedly display a user even if the ticket was previously unassigned or assigned to a different user. This occurred because:

1. The backend applies topic-specific auto-assignment rules when a ticket's topic is changed
2. After changing the topic via API, refreshTicket() fetches the updated ticket data from the server
3. The server response includes the auto-assigned user based on topic rules
4. The UI reflects this server-assigned user, even though the user only intended to change the topic

This behavior was confusing because users expect the assignee to remain unchanged when they're only modifying the topic field.

Solution

Added logic to preserve the original assignee when changing a ticket's topic:

• Introduced a changingTopic flag to track when a topic change operation is in progress
• When handleTopicChanged() initiates a topic change, the flag is set and the current assignee is preserved
• When refreshTicket() receives the updated ticket data, it restores the preserved assignee instead of accepting the server's auto-assigned user
• The flag is cleared after the operation completes

This ensures that the assignee widget only changes when the user explicitly assigns/unassigns a ticket through the assignee control, not as a side effect of changing the topic.

Testing

Added two comprehensive tests to verify the fix:

1. Unassigned ticket remains unassigned after topic change (even when server auto-assigns)
2. Existing assignee is preserved when topic changes (even when server attempts to reassign)

All 919 tests pass with 82.11% coverage.

Fixes the issue where changing a ticket topic would unexpectedly modify the assignee.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• example.com
  • Triggering command: /home/REDACTED/work/temba-components/temba-components/node_modules/puppeteer/.local-chromium/linux-982053/chrome-linux/chrome --disable-REDACTED-networking --enable-features=NetworkService,NetworkServiceInProcess --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-features=Translate,BackForwardCache --disable-hang-monitor --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-sync --force-color-profile=srgb --metrics-recording-only --no-first-run --enable-automation --password-store=basic --use-mock-keychain --enable-blink-features=IdleDetection --export-tagged-pdf --headless --hide-scrollbars --mute-audio --font-render-hinting=medium --force-color-profile=srgb --hide-scrollbars --disable-web-security --force-device-scale-factor=1 --no-sandbox --disable-gpu --disable-font-subpixel-positioning --disable-lcd-text --force-prefers-reduced-motion --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-renderer-REDACTEDing --disable-gpu-sandbox --disable-software-rasterizer --disable-REDACTED-networking --disable-default-apps --disable-extensions --disable-sync --disable-translate --hide-crash-restore-bubble --metrics-recording-only --no-first-run --safebrowsing-disable-auto-update --use-mock-keychain --disable-ipc-flooding-protection --disable-component-update --disable-domain-reliability --remote-debugging-port=0 --user-data-dir=/tmp/puppeteer_dev_chrome_profile-3NheMt about:blank (dns block)
  • Triggering command: /home/REDACTED/work/temba-components/temba-components/node_modules/puppeteer/.local-chromium/linux-982053/chrome-linux/chrome --disable-REDACTED-networking --enable-features=NetworkService,NetworkServiceInProcess --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-features=Translate,BackForwardCache --disable-hang-monitor --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-sync --force-color-profile=srgb --metrics-recording-only --no-first-run --enable-automation --password-store=basic --use-mock-keychain --enable-blink-features=IdleDetection --export-tagged-pdf --headless --hide-scrollbars --mute-audio --font-render-hinting=medium --force-color-profile=srgb --hide-scrollbars --disable-web-security --force-device-scale-factor=1 --no-sandbox --disable-gpu --disable-font-subpixel-positioning --disable-lcd-text --force-prefers-reduced-motion --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-renderer-REDACTEDing --disable-gpu-sandbox --disable-software-rasterizer --disable-REDACTED-networking --disable-default-apps --disable-extensions --disable-sync --disable-translate --hide-crash-restore-bubble --metrics-recording-only --no-first-run --safebrowsing-disable-auto-update --use-mock-keychain --disable-ipc-flooding-protection --disable-component-update --disable-domain-reliability --remote-debugging-port=0 --user-data-dir=/tmp/puppeteer_dev_chrome_profile-6MdYa8 about:blank (dns block)
  • Triggering command: /home/REDACTED/work/temba-components/temba-components/node_modules/puppeteer/.local-chromium/linux-982053/chrome-linux/chrome --disable-REDACTED-networking --enable-features=NetworkService,NetworkServiceInProcess --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-default-apps --disable-dev-shm-usage --disable-extensions --disable-features=Translate,BackForwardCache --disable-hang-monitor --disable-ipc-flooding-protection --disable-popup-blocking --disable-prompt-on-repost --disable-renderer-REDACTEDing --disable-sync --force-color-profile=srgb --metrics-recording-only --no-first-run --enable-automation --password-store=basic --use-mock-keychain --enable-blink-features=IdleDetection --export-tagged-pdf --headless --hide-scrollbars --mute-audio --font-render-hinting=medium --force-color-profile=srgb --hide-scrollbars --disable-web-security --force-device-scale-factor=1 --no-sandbox --disable-gpu --disable-font-subpixel-positioning --disable-lcd-text --force-prefers-reduced-motion --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-renderer-REDACTEDing --disable-gpu-sandbox --disable-software-rasterizer --disable-REDACTED-networking --disable-default-apps --disable-extensions --disable-sync --disable-translate --hide-crash-restore-bubble --metrics-recording-only --no-first-run --safebrowsing-disable-auto-update --use-mock-keychain --disable-ipc-flooding-protection --disable-component-update --disable-domain-reliability --remote-debugging-port=0 --user-data-dir=/tmp/puppeteer_dev_chrome_profile-K8CKDz about:blank (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Bug in ticket assignee widget</issue_title>
<issue_description>1. Go to unassigned ticket
2. Change topic
3. Assignee widget switches to a user</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #692

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.