Add application read models and thin TUI command adapter

src/app/first_delivery.rs

@@ -39,6 +39,17 @@ enum IssueStage {
     RetryNeedsManualCleanup,
 }
 
+/// Read-only first-file availability with no access to the held private key,
+/// issue context, or payload.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub(super) enum SessionFirstDeliveryAvailability {
+    InitialFile,
+    Retry,
+    RetryNeedsOverwriteConfirmation,
+    RetryNeedsManualCleanup,
+    Unavailable,
+}
+
 pub(super) struct FirstIssueAuthorization {
     identity: PublicKey,
     context: IssueContext,
@@ -64,6 +75,36 @@ impl FirstDeliverySession {
         self.issues.len()
     }
 
+    pub(super) fn read_model_availability(
+        &self,
+        identity: PublicKey,
+        document: &ConfigDocument,
+        vault: Option<&VaultBundle>,
+    ) -> SessionFirstDeliveryAvailability {
+        let Some(issue) = self.issues.get(&identity) else {
+            return SessionFirstDeliveryAvailability::Unavailable;
+        };
+        let matching = vault
+            .and_then(|vault| context_for(document, vault, identity).ok())
+            .is_some_and(|actual| actual == issue.context);
+        if !matching {
+            return SessionFirstDeliveryAvailability::Unavailable;
+        }
+        match issue.stage {
+            IssueStage::AwaitingFirstFile => SessionFirstDeliveryAvailability::InitialFile,
+            IssueStage::RetryAvailable => SessionFirstDeliveryAvailability::Retry,
+            IssueStage::RetryNeedsOverwriteConfirmation => {
+                SessionFirstDeliveryAvailability::RetryNeedsOverwriteConfirmation
+            }
+            IssueStage::RetryNeedsManualCleanup => {
+                SessionFirstDeliveryAvailability::RetryNeedsManualCleanup
+            }
+            IssueStage::PendingDraft | IssueStage::Authorizing(_) => {
+                SessionFirstDeliveryAvailability::Unavailable
+            }
+        }
+    }
+
     #[cfg(test)]
     pub(super) fn is_empty(&self) -> bool {
         self.issues.is_empty()