[PM-36011] feat: add member email change notification email

[jrmccannon]

🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-36011

📔 Objective

Adds the "Your Bitwarden account email was updated" notification email (part of PM-28365), built with the IMailer / MJML pipeline: view model, mail class, MJML source, compiled templates, and a render test.

Sending isn't wired up yet. Hero asset (spot-enterprise-gear.svg) is added in bitwarden/assets#28.

TODO: once #7964 (PM-38926) merges, wire up the sending side effect in the v2 UpdateOrganizationUser command.

[github-actions]

🤖 Bitwarden Claude Code Review

Overall Assessment: APPROVE

Reviewed the new "member email changed" notification email: view model (MemberEmailChangedNotificationView / MemberEmailChangedNotificationMail), MJML source, compiled HTML/text templates, and a render test. The change follows the existing IMailer/BaseMail + Handlebars conventions used by sibling AdminConsole mailers, and the referenced MJML components (mj-bw-ac-hero, mj-bw-ac-learn-more-footer, head/footer includes) all exist. The .hbs files embed via the existing **\*.hbs glob and their namespace matches the folder path, so template resolution by GetType().FullName works as verified by the render test.

No security or correctness issues found. {{NewEmail}} uses double-stache Handlebars interpolation, which HTML-escapes by default, so the user-supplied email value cannot inject markup. Sending is intentionally not wired up yet (tracked as a follow-up per the PR description), and the header-asset TODO(PM-36011) is intentional and tracked.

Code Review Details

No findings.

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 62.12%. Comparing base (14fee75) to head (b118fb3).
⚠️ Report is 19 commits behind head on main.

Files with missing lines	Patch %	Lines
...EmailChanged/MemberEmailChangedNotificationView.cs	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7990      +/-   ##
==========================================
- Coverage   66.13%   62.12%   -4.02%     
==========================================
  Files        2256     2285      +29     
  Lines       99392    99668     +276     
  Branches     8983     9016      +33     
==========================================
- Hits        65732    61916    -3816     
- Misses      31409    35577    +4168     
+ Partials     2251     2175      -76     

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