fix(rchoices): hide tab labels on mobile, show icons only

Also adds backlog task for rTasks email checklist HMAC flow.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backlog/tasks/task-high.6 - rtasks-email-checklist-—-HMAC-signed-clickable-AC-items-from-email.md

@@ -0,0 +1,27 @@
+---
+id: TASK-HIGH.6
+title: rtasks email checklist — HMAC-signed clickable AC items from email
+status: Done
+assignee: []
+created_date: '2026-03-16 19:28'
+updated_date: '2026-03-16 19:28'
+labels:
+  - rtasks
+  - email
+  - checklist
+  - backlog
+dependencies: []
+parent_task_id: TASK-HIGH
+---
+
+## Description
+
+<!-- SECTION:DESCRIPTION:BEGIN -->
+Email checklist micro-service integrated into rspace-online rtasks module. Sends emails with HMAC-signed links for each backlog task acceptance criterion. Clicking a link toggles the AC in the markdown file and re-renders a confirmation page. Routes: GET /rtasks/check/:token (verify + toggle + render), POST /api/rtasks/send (build + send email). Uses Web Crypto HMAC-SHA256 tokens, direct markdown AC parsing, Nodemailer via Mailcow SMTP (noreply@rmail.online). Mounted at top-level in server/index.ts to bypass space auth middleware.
+<!-- SECTION:DESCRIPTION:END -->
+
+## Implementation Notes
+
+<!-- SECTION:NOTES:BEGIN -->
+Implemented and deployed. Routes at /rtasks/check/:token and /api/rtasks/send. Infisical secrets: RTASKS_HMAC_SECRET, RTASKS_API_KEY. SMTP via mailcowdockerized-postfix-mailcow-1 as noreply@rmail.online. Volume mount /opt/dev-ops:/repos/dev-ops for task file access. E2E tested successfully — email sends, link toggles AC, page re-renders. Commits: integrated into rspace-online (not standalone).
+<!-- SECTION:NOTES:END -->