feat: cost-guarded resumable index build (sample smoke + full)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/bin/alpha_id.rs

@@ -52,9 +52,48 @@ fn main() {
     let cfg = Config::load(&cli.config).expect("config");
     match cli.cmd {
         Cmd::Index { sample, full, confirm } => {
+            use alpha_id::embed::{EmbeddingStore, build_corpus_embeddings, estimate};
+            use alpha_id::ionos::IonosClient;
             let p = Pipeline::load(&cfg).expect("load");
-            eprintln!("Loaded {} entries, {} ICD metas. (sample={:?} full={} confirm={})",
-                p.entries.len(), p.meta.len(), sample, full, confirm);
+            let texts: Vec<String> = p.entries.iter().map(|e| e.text.clone()).collect();
+            let client = IonosClient::new(&cfg.ionos_base_url, &cfg.token_path)
+                .expect("ionos client (token?)");
+            let store = EmbeddingStore::open(&cfg.index_dir, &cfg.embed_model).expect("store");
+
+            let subset: Vec<String> = match sample {
+                Some(n) => texts.iter().take(n).cloned().collect(),
+                None => texts.clone(),
+            };
+
+            if sample.is_some() {
+                let est = estimate(&subset);
+                eprintln!("SMOKE: embedding {} sample texts ({} chars)…", est.items, est.chars);
+                let n = build_corpus_embeddings(&client, &store, &cfg.embed_model, &subset, 32)
+                    .expect("sample embed failed");
+                let dim = store.get(&subset[0]).map(|v| v.len()).unwrap_or(0);
+                eprintln!("SMOKE OK: embedded {n}, vector dim = {dim}. \
+                           Inspect, then run `index --full --confirm`.");
+                return;
+            }
+
+            if full {
+                let pending: Vec<String> = texts.iter().filter(|t| !store.has(t)).cloned().collect();
+                let est = estimate(&pending);
+                eprintln!("FULL RUN: {} of {} texts not yet embedded ({} chars). \
+                           This calls IONOS and costs money.", est.items, texts.len(), est.chars);
+                if !confirm {
+                    eprintln!("Refusing without --confirm. Re-run: \
+                               `alpha-id index --full --confirm`");
+                    std::process::exit(2);
+                }
+                let n = build_corpus_embeddings(&client, &store, &cfg.embed_model, &texts, 32)
+                    .expect("full embed failed");
+                eprintln!("FULL RUN done: {n} newly embedded, {} total cached.",
+                    texts.iter().filter(|t| store.has(t)).count());
+                return;
+            }
+
+            eprintln!("Specify --sample N (smoke test first) or --full --confirm.");
         }
         Cmd::Suggest { input, mode, top, billable_only, valid_only, exclude_exotic, chapters, json } => {
             let p = Pipeline::load(&cfg).expect("load");