Ensure transcript parser consumes entire stanzas

With the switch to `cmark`, the “second phase” parsing of individual
stanzas omitted an EOF check to ensure that the entire stanza had been
parsed. This resulted in parses where we end up with truncated sets of
UCM commands or API requests, which could either result in premature
success or failures occurring later in the transcript, where they’d
complain about the wrong thing.

unison-cli/src/Unison/Codebase/Transcript/Parser.hs

@@ -24,11 +24,10 @@ where
 import CMark qualified
 import Data.Char qualified as Char
 import Data.Text qualified as Text
-import Data.These (These (..))
 import Text.Megaparsec qualified as P
 import Unison.Codebase.Transcript
 import Unison.Prelude
-import Unison.Project (ProjectAndBranch (ProjectAndBranch))
+import Unison.Project (fullyQualifiedProjectAndBranchNamesParser)
 
 formatAPIRequest :: APIRequest -> Text
 formatAPIRequest = \case
@@ -72,24 +71,16 @@ ucmLine :: P UcmLine
 ucmLine = ucmCommand <|> ucmComment
   where
     ucmCommand :: P UcmLine
-    ucmCommand = do
-      context <-
-        P.try do
-          contextString <- P.takeWhile1P Nothing (/= '>')
-          context <-
-            case (tryFrom @Text contextString) of
-              (Right (These project branch)) -> pure (UcmContextProject (ProjectAndBranch project branch))
-              _ -> fail "expected project/branch or absolute path"
-          void $ lineToken $ word ">"
-          pure context
-      line <- P.takeWhileP Nothing (/= '\n') <* spaces
-      pure $ UcmCommand context line
+    ucmCommand =
+      UcmCommand
+        <$> fmap UcmContextProject (P.try $ fullyQualifiedProjectAndBranchNamesParser <* lineToken (word ">"))
+        <*> P.takeWhileP Nothing (/= '\n')
+        <* spaces
 
     ucmComment :: P UcmLine
-    ucmComment = do
-      word "--"
-      line <- P.takeWhileP Nothing (/= '\n') <* spaces
-      pure $ UcmComment line
+    ucmComment =
+      P.label "comment (delimited with “--”)" $
+        UcmComment <$> (word "--" *> P.takeWhileP Nothing (/= '\n')) <* spaces
 
 apiRequest :: P APIRequest
 apiRequest = do
@@ -118,7 +109,7 @@ fenced info = do
       hide <- hidden
       err <- expectingError
       P.setInput body
-      pure . Ucm hide err <$> (spaces *> many ucmLine)
+      pure . Ucm hide err <$> (spaces *> P.manyTill ucmLine P.eof)
     "unison" ->
       do
         -- todo: this has to be more interesting
@@ -132,7 +123,7 @@ fenced info = do
         pure . Unison hide err fileName <$> (spaces *> P.getInput)
     "api" -> do
       P.setInput body
-      pure . API <$> (spaces *> many apiRequest)
+      pure . API <$> (spaces *> P.manyTill apiRequest P.eof)
     _ -> pure Nothing
 
 word :: Text -> P Text