fix(templates): cross-validate against official Gitea mail templates

- Fix INK theme: replace .ActiveCodeLives with correct field, remove from non-auth contexts (8 files)
- Fix hardcoded button text: use locale key mail.view_it_on in ember, heritage, ink, mono, terminal, terra (30+ files)
- Add missing {{if .CanReply}}mail.reply{{end}} block to all 10 themes default.tmpl
- Add missing mail.release.note locale label to all 10 themes release.tmpl
- Add missing mail.team_invite.text_3 to ink and terra team_invite.tmpl
- Add missing blockquote CSS to aurora, ink, mono, neon, terra default.tmpl

Verified: all 110 templates compile successfully with Go build-preview.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

themes/terminal/mail/repo/release.tmpl

@@ -35,6 +35,7 @@
 
         <h4 style="margin:20px 0 8px; font-size:16px; font-weight:700; color:#00ff41;">{{.locale.Tr "mail.release.title" .Release.Title}}</h4>
 
+        <p style="margin:0 0 8px;font-weight:700;color:#00ff41;">$ {{.locale.Tr "mail.release.note"}}</p>
         {{if .Release.RenderedNote}}
           <div style="margin:12px 0 16px; font-size:14px; line-height:1.6; color:#c9d1d9;">
             {{.Release.RenderedNote}}
@@ -63,7 +64,7 @@
         <table border="0" cellpadding="0" cellspacing="0" width="100%" style="margin:16px 0 20px; border-collapse:separate;">
           <tr>
             <td align="left">
-              <a href="{{.Link}}" style="display:inline-block; padding:11px 24px; font-size:14px; font-weight:700; color:#0d1117; text-decoration:none; background-color:#00ff41; border:2px solid #00ff41; font-family:'JetBrains Mono','Fira Code','Consolas',monospace; letter-spacing:0.5px;">$ view_release</a>
+              <a href="{{.Link}}" style="display:inline-block; padding:11px 24px; font-size:14px; font-weight:700; color:#0d1117; text-decoration:none; background-color:#00ff41; border:2px solid #00ff41; font-family:'JetBrains Mono','Fira Code','Consolas',monospace; letter-spacing:0.5px;">{{.locale.Tr "mail.view_it_on" AppName}}</a>
             </td>
           </tr>
         </table>