Add BLS client library, example scripts, and usage docs

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

examples/basic_pull.py

@@ -0,0 +1,43 @@
+"""
+Basic example — fetch a few series and print the latest values.
+Run from the bls/ directory:  python3 examples/basic_pull.py
+"""
+
+import sys, os
+sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
+
+from config import BLS_API_KEY
+from bls_client import BLSClient
+from bls_client.queries import employment, prices, wages
+
+client = BLSClient(BLS_API_KEY)
+
+# ── Single series ────────────────────────────────────────────────────────────
+print("=== National Nonfarm Payrolls ===")
+result = client.fetch_latest(employment.nonfarm_payrolls(), years=1)
+for sid, s in result.items():
+    obs = client.latest_obs(s)
+    print(f"  {obs['periodName']} {obs['year']}: {float(obs['value']):,.0f} thousand jobs")
+
+# ── Named dict pull ──────────────────────────────────────────────────────────
+print("\n=== CPI Dashboard (latest month) ===")
+results = client.fetch_named(prices.cpi_dashboard(), 2025, 2026)
+for label, s in results.items():
+    obs = client.latest_obs(s)
+    if obs:
+        print(f"  {label:<30} {obs['value']:>8}  ({obs['periodName']} {obs['year']})")
+
+# ── DC region unemployment ───────────────────────────────────────────────────
+print("\n=== DC Region Unemployment Rates ===")
+results = client.fetch_named(employment.dc_region_unemployment(), 2025, 2026)
+for label, s in results.items():
+    obs = client.latest_obs(s)
+    if obs:
+        print(f"  {label:<20} {obs['value']}%  ({obs['periodName']} {obs['year']})")
+
+# ── Flatten to rows ──────────────────────────────────────────────────────────
+print("\n=== Raw rows (first 3) ===")
+result = client.fetch_latest(employment.nonfarm_payrolls(), years=1, catalog=True)
+rows = client.to_rows(result)
+for row in rows[:3]:
+    print(f"  {row}")