fix: UI overhaul — align all HTMX views with Lumina Design System (46 fixes)

- All 7 pages rewritten: Dashboard, Terminal, Snippets, Keychain, SFTP, Settings, Brief
- Apply consistent Lumina glassmorphic theme (rounded-2xl, shadows, borders, tracking)
- Fix SVG icons not rendering — return template.HTML instead of string
- Fix Alpine x-data scoping: terminal tabs, SFTP modals, snippet tag buttons
- Fix dashboard search sending literal ?q=...
- Rebuild CSS with all new Tailwind classes (62KB)
- Add .air.toml with hot-reload config, docs/PERBAIKANUI.md checklist
- Remove unused backup partials

app/backend/internal/handler/keychain.go

@@ -8,6 +8,9 @@ import (
 var keyStore = store.NewKeyStore()
 
 func Keychain(c *fiber.Ctx) error {
+	if c.Get("HX-Request") != "" {
+		return KeyGrid(c)
+	}
 	keys := keyStore.All()
 	return c.Render("keychain", fiber.Map{
 		"View":      "keychain",