build: stages in the plan's own words

`stages_text` on a need gives each stage plain words in the plan's
language. The fallback mails, the road line and the desk buttons use
them, and needs.yaml carries them as `stage_words` so the desk score
describes an outcome the way the site would. The vel's plan has them;
its desks score 26 of 26 where the id-based outcome scored 24.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/rate.rs

@@ -187,8 +187,10 @@ fn s(v: &Value) -> String {
 /// the button for it. The outcome is put in plain words from the
 /// state's own name, never from the label, and the buttons are listed
 /// in a seeded shuffle.
-fn button_pick(cmd: &str, group: &str, bucket: &str, from: &str, to: &str, labels: &[&str], seed: usize) -> anyhow::Result<String> {
-    let plain = |id: &str| id.replace(['_', '-'], " ");
+fn button_pick(cmd: &str, group: &str, bucket: &str, from: &str, to: &str, labels: &[&str], seed: usize, words: &Value) -> anyhow::Result<String> {
+    // The state in the plan's own words when the spec carries them,
+    // else the id made readable.
+    let plain = |id: &str| words[id].as_str().map(str::to_string).unwrap_or_else(|| id.replace(['_', '-'], " "));
     let mut order: Vec<&str> = labels.to_vec();
     // A fixed rotation per move: the right answer is not always first.
     let by = seed % order.len().max(1);
@@ -319,7 +321,7 @@ pub fn rate(argv: &[String]) -> anyhow::Result<()> {
                     continue;
                 }
                 asked += 1;
-                let picked = button_pick(&cmd, group, bucket, from, to, &labels, i)?;
+                let picked = button_pick(&cmd, group, bucket, from, to, &labels, i, &model["buckets"][bucket]["words"])?;
                 if picked == *label {
                     right += 1;
                 } else {