cli: Fix accidental issue creation

When a user is creating an issue via the editor, it is very easy to
accidentally create an issue.

To fix this, make the default description also 'empty' and bail out if
either it or the title are empty.

Retain the default 'description' message by providing it as a comment.

radicle-cli/src/commands/issue.rs

@@ -1,5 +1,6 @@
 #![allow(clippy::or_fun_call)]
 use std::ffi::OsString;
+use std::io;
 use std::str::FromStr;
 
 use anyhow::{anyhow, Context as _};
@@ -464,7 +465,9 @@ fn prompt_issue(
         title
     };
     let description = if description.is_empty() {
-        "Enter a description..."
+        "<!--\n\
+        Enter a description...\n\
+        -->"
     } else {
         description
     };
@@ -500,10 +503,28 @@ fn prompt_issue(
         }
     }
 
-    let description: String = lines.collect::<Vec<&str>>().join("\n");
-    let meta: Metadata =
+    let mut meta: Metadata =
         serde_yaml::from_str(&meta).context("failed to parse yaml front-matter")?;
 
+    meta.title = meta.title.trim().to_string();
+    if meta.title.is_empty() {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            "an issue title must be provided",
+        )
+        .into());
+    }
+
+    let description: String = lines.collect::<Vec<&str>>().join("\n");
+    let description = term::format::strip_comments(&description);
+    if description.is_empty() {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            "an issue description must be provided",
+        )
+        .into());
+    }
+
     Ok(Some((meta, description)))
 }