fix: prevent blank page on rebuild and queue drain on skip/discard

Two bugs fixed:

1. Blank white page after vue SPA rebuild: browsers cached old index.html
   referencing old asset hashes. Assets are deleted on rebuild, causing
   404s for JS/CSS -> blank page. Fix: serve index.html with
   Cache-Control: no-cache so browsers always fetch fresh HTML.
   Hashed assets (/assets/chunk-abc123.js) remain cacheable forever.

2. Queue draining to empty on skip/discard: handleSkip and handleDiscard
   never refilled the local queue buffer. After enough skips, store.current
   went null and the empty state showed (blank-looking). Fix: both handlers
   now call fetchBatch() when queue drops below 3, matching handleLabel.

Also: sync classifier_adapters LABELS to match current 10-label schema
(new_lead + hired, remove unrelated).

48 Python tests pass, 48 frontend tests pass.

app/api.py

@@ -209,5 +209,16 @@ def get_labels():
 # Static SPA — MUST be last (catches all unmatched paths)
 _DIST = _ROOT / "web" / "dist"
 if _DIST.exists():
+    from fastapi.responses import FileResponse
     from fastapi.staticfiles import StaticFiles
+
+    # Serve index.html with no-cache so browsers always fetch fresh HTML after rebuilds.
+    # Hashed assets (/assets/index-abc123.js) can be cached forever — they change names
+    # when content changes (standard Vite cache-busting strategy).
+    _NO_CACHE = {"Cache-Control": "no-cache, no-store, must-revalidate", "Pragma": "no-cache"}
+
+    @app.get("/")
+    def get_spa_root():
+        return FileResponse(str(_DIST / "index.html"), headers=_NO_CACHE)
+
     app.mount("/", StaticFiles(directory=str(_DIST), html=True), name="spa")

scripts/classifier_adapters.py

@@ -27,8 +27,9 @@ LABELS: list[str] = [
     "survey_received",
     "neutral",
     "event_rescheduled",
-    "unrelated",
     "digest",
+    "new_lead",
+    "hired",
 ]
 
 # Natural-language descriptions used by the RerankerAdapter.
@@ -40,8 +41,9 @@ LABEL_DESCRIPTIONS: dict[str, str] = {
     "survey_received": "invitation to complete a culture-fit survey or assessment",
     "neutral": "automated ATS confirmation such as application received",
     "event_rescheduled": "an interview or scheduled event moved to a new time",
-    "unrelated": "non-job-search email unrelated to any application or recruiter",
     "digest": "job digest or multi-listing email with multiple job postings",
+    "new_lead": "unsolicited recruiter outreach or cold contact about a new opportunity",
+    "hired": "job offer accepted, onboarding logistics, welcome email, or start date confirmation",
 }
 
 # Lazy import shims — allow tests to patch without requiring the libs installed.

tests/test_classifier_adapters.py

@@ -2,14 +2,16 @@
 import pytest
 
 
-def test_labels_constant_has_nine_items():
+def test_labels_constant_has_ten_items():
     from scripts.classifier_adapters import LABELS
-    assert len(LABELS) == 9
+    assert len(LABELS) == 10
     assert "interview_scheduled" in LABELS
     assert "neutral" in LABELS
     assert "event_rescheduled" in LABELS
-    assert "unrelated" in LABELS
     assert "digest" in LABELS
+    assert "new_lead" in LABELS
+    assert "hired" in LABELS
+    assert "unrelated" not in LABELS
 
 
 def test_compute_metrics_perfect_predictions():

web/src/views/LabelView.vue

@@ -211,6 +211,7 @@ async function handleSkip() {
     headers: { 'Content-Type': 'application/json' },
     body: JSON.stringify({ id: item.id }),
   })
+  if (store.queue.length < 3) await fetchBatch()
 }
 
 async function handleDiscard() {
@@ -228,6 +229,7 @@ async function handleDiscard() {
     headers: { 'Content-Type': 'application/json' },
     body: JSON.stringify({ id: item.id }),
   })
+  if (store.queue.length < 3) await fetchBatch()
 }
 
 async function handleUndo() {