fix(acp-agents): hide remote servers without deleting

[wgqqqqq]

Summary

Fixes #2035.

• adds a reversible hide action for saved remote servers on the ACP Agents settings page
• keeps the underlying saved SSH connection, credentials, and Remote Connect behavior unchanged
• persists hidden connection IDs as a client-local UI preference
• provides a Hidden servers entry for restoring individual servers
• skips remote ACP requirement probes while a server is hidden
• adds localized copy for en-US, zh-CN, and zh-TW

Rationale

Removing a server from the ACP Agents view should not delete the shared SSH connection. This provides a reversible alternative to the destructive behavior proposed in #2122.

Validation

• pnpm --dir src/web-ui run test:run src/infrastructure/config/components/AcpAgentsConfig.test.tsx (10 passed)
• pnpm run type-check:web
• pnpm run i18n:audit (0 warnings)
• pnpm --dir src/web-ui exec eslint src/infrastructure/config/components/AcpAgentsConfig.tsx
• git diff --check

AI assistance

AI-assisted implementation; fully tested with the commands above.