fix: zsh pass empty partial when no positional args exist

When _arguments -C resets $words to only positional args and there
are none yet (user pressed TAB after 'sentry issue list '), the
empty words array caused 'list' to be misinterpreted as the partial.
Now conditionally appends an empty string only when words is empty.

Author: BYK

src/lib/completions.ts

@@ -443,7 +443,13 @@ ${caseBranches}
         else
           completions+=("\${value}")
         fi
-      done < <(${binaryName} __complete "$line[1]" "$line[2]" "\${words[@]}" 2>/dev/null)
+      done < <(
+        if (( \${#words} == 0 )); then
+          ${binaryName} __complete "$line[1]" "$line[2]" "" 2>/dev/null
+        else
+          ${binaryName} __complete "$line[1]" "$line[2]" "\${words[@]}" 2>/dev/null
+        fi
+      )
       if (( \${#completions} )); then
         _describe -t values 'value' completions
       fi