feat(mail): add reply and move action

[keilogic]

Closes #1451

Summary

• Add an RMM7 "Reply and move" message menu action that opens the folder picker, moves the open message, then opens a reply draft.
• Reuse the existing move-to-folder local and remote update behavior through a shared helper so the normal "Move to folder" action keeps the same behavior.
• Add the required MessageActions interface method, RMM6 unsupported placeholder, and unit coverage for the new flow.

Tests

• Red baseline: npx ng test runbox7 --watch=false --browsers=FirefoxHeadless --include=src/app/mailviewer/rmm7messageactions.spec.ts failed before the implementation with TypeError: actions.replyAndMove is not a function and TOTAL: 1 FAILED, 0 SUCCESS
• npx ng test runbox7 --watch=false --browsers=FirefoxHeadless --include=src/app/mailviewer/rmm7messageactions.spec.ts
• npx ng test runbox7 --watch=false --browsers=FirefoxHeadless --include=src/app/mailviewer/singlemailviewer.component.spec.ts
• npx tsc -p src/tsconfig.app.json --noEmit
• npx tsc -p src/tsconfig.spec.json --noEmit
• npm run lint -- --quiet
• npm run policy
• git diff --check origin/master...HEAD
• $env:SKIP_CHANGELOG='1'; node src/build/pre-build.js; npx ng build --configuration production --base-href=/app/ runbox7; node src/build/post-build.js

AI disclosure

• Used OpenAI Codex in C:\Users\admin\Desktop\money-v3\En cours\runbox7-reply-and-move-1451 for implementation and validation assistance.