feat: share env files as encrypted links

S → f on a repo, an env file or a key in one copies a
lazysecrets://share link holding the env files, encrypted (age) with
a secret's value: whoever can read that secret can open it. The key is
share.key in the repo's .lazysecrets.yaml, else in the config, else
picked when sharing; on Azure the link pins its version. Opening one
says what it holds, decrypts when asked, and saves the files in the
clone of the repo (or a folder chosen), replacing existing ones only
when asked. lazysecrets share prints a link from the command line.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

internal/ui/app/links.go

@@ -78,6 +78,9 @@ const (
 // just open it.
 // With ask false, vault and scope links open straight away.
 func (m *Model) offerRef(title string, r ref.Ref, ask bool) tea.Cmd {
+	if r.IsShare() {
+		return m.offerShare(r)
+	}
 	if r.IsContainer() || r.IsSource() {
 		if !ask {
 			return m.openRef(r, actGo)
@@ -607,6 +610,9 @@ func (m *Model) share(menu bool) tea.Cmd {
 		if s.URL != "" {
 			opts = append(opts, option{key: "b", label: webLabel(s.Kind), run: share("b")})
 		}
+		if m.canShareFiles(s) {
+			opts = append(opts, option{key: "f", label: "Encrypted link to its env files", run: func(m *Model) tea.Cmd { return m.shareFiles(s, nil) }})
+		}
 		m.showMenu("Share "+s.Name, nil, opts)
 	case paneContainers:
 		c, ok := m.containers.Selected()
@@ -629,6 +635,11 @@ func (m *Model) share(menu bool) tea.Cmd {
 		if c.URL != "" {
 			opts = append(opts, option{key: "b", label: webLabel(c.Source.Kind), run: share("b")})
 		}
+		if c.Detail == provider.DetailPlainEnv && m.canShareFiles(c.Source) {
+			opts = append(opts, option{key: "f", label: "Encrypted link to the file", run: func(m *Model) tea.Cmd {
+				return m.shareFiles(c.Source, []provider.Container{c})
+			}})
+		}
 		m.showMenu("Share "+c.Name, nil, opts)
 	default:
 		o, ok := m.detail.Secret()
@@ -653,6 +664,11 @@ func (m *Model) share(menu bool) tea.Cmd {
 		if o.URL != "" {
 			opts = append(opts, option{key: "b", label: webLabel(o.Container.Source.Kind), run: share("b")})
 		}
+		if c := o.Container; c.Detail == provider.DetailPlainEnv && m.canShareFiles(c.Source) {
+			opts = append(opts, option{key: "f", label: "Encrypted link to its file", run: func(m *Model) tea.Cmd {
+				return m.shareFiles(c.Source, []provider.Container{c})
+			}})
+		}
 		m.showMenu("Share "+o.Name, nil, opts)
 	}
 	return nil