memoryd: sync begins when Honcho is turned on, and conclusions are matched by peer

Co-Authored-By: ornith-1.5-35b-a3b <agent@wntrmute.dev>

crates/memoryd/tests/support/ledger.rs

@@ -28,6 +28,14 @@ impl Home {
         Ledger::open(&self.path).unwrap()
     }
 
+    /// A new ledger that has begun (`began()`): what `memoryd` makes at its first start, and so
+    /// what a test that reads its ledger back needs (M5c-1 task 15).
+    pub fn begun(&self) -> Ledger {
+        let mut ledger = self.open();
+        ledger.append(began()).unwrap();
+        ledger
+    }
+
     /// The file's bytes as text; "" when there is no file.
     pub fn text(&self) -> String {
         std::fs::read_to_string(&self.path).unwrap_or_default()
@@ -85,13 +93,25 @@ pub fn conclude(workspace: Workspace, text: &str) -> Action {
     }
 }
 
+/// The deletion of the owner's (`kyle`'s) conclusion `text`, as `conclude` makes it.
 pub fn unconclude(workspace: Workspace, text: &str) -> Action {
     Action::Unconclude {
         workspace,
+        peer: "kyle".to_string(),
         text: text.to_string(),
     }
 }
 
+/// When sync began, `TIME`.
+pub fn began() -> Record {
+    Record::Began { time: time() }
+}
+
+/// `began()`'s line.
+pub fn began_line() -> String {
+    line(&began())
+}
+
 pub fn decided(item: &Item, action: Action) -> Record {
     Record::Decided {
         time: time(),