🐛 Bugfix: fix status tag icon misalignment and localize auth dialog slogan

[ayiya12]

Summary

This PR includes two frontend UI bug fixes:

1. Fix status tag icon misalignment in resource-manage lists — Fixed incorrect icon alignment in AgentList, InvitationList, McpList, and ModelList by replacing className shortcuts with explicit inline styles (display: inline-flex, alignItems: center, flexShrink: 0) and wrapping icons in <span className="inline-flex items-center mr-1"> to ensure Lucide icons and Tag content render correctly across all status variants.

2. Localize auth dialog slogan for zh and en — Replaced the hardcoded English slogan string in AuthDialogs.tsx with a t("page.loginPrompt.slogan") i18n key, added the corresponding Chinese translation in zh/common.json, and updated generateMetadata in layout.tsx to return a locale-aware page description. Fix [Improvement] Login page globalization #2936

---

Changes

UI alignment fix

• AgentList.tsx — Unpublished agent tag icon alignment
• McpList.tsx — MCP server availability tags, health check loader tags
• ModelList.tsx — Model status tags (available, unavailable, detecting, not_detected)
• InvitationList.tsx — Invitation status tags (IN_USE, EXPIRE, RUN_OUT)

i18n fix

• AuthDialogs.tsx — Use t("page.loginPrompt.slogan") instead of hardcoded string
• layout.tsx — Return locale-aware description in metadata
• en/common.json — Add "page.loginPrompt.slogan"
• zh/common.json — Add "page.loginPrompt.slogan" with Chinese text

---

Testing

• Manual browser verification on both zh and en locales
• All four resource management pages render status tags correctly at various container widths