docs: apply fleet-template (16-artifact scaffold)

Adds missing standard artifacts:
- README.md (if missing)
- AGENTS.md (AI agent contract)
- PLAN.md (current sprint)
- STATUS.md (where we are)
- DEVELOPMENT.md (dev workflow)
- DEPLOYMENT.md (deploy procedure)
- TESTING.md (test strategy)
- DECISIONS.md (ADR index + templates)
- .github/CODEOWNERS
- .github/workflows/ci.yml

Preserves all existing artifacts.

Refs: RugMunchMedia/fleet-template

tests/test_freshness.py

@@ -0,0 +1,45 @@
+"""Tests for adaptive freshness scheduling."""
+
+from freshness import (
+    calculate_adaptive_frequency,
+    check_content_changed,
+    compute_content_hash,
+    record_check_result,
+)
+
+
+def test_content_hash_consistent() -> None:
+    h1 = compute_content_hash("Hello   World")
+    h2 = compute_content_hash("Hello World")
+    assert h1 == h2  # Whitespace normalization
+
+
+def test_content_hash_differs() -> None:
+    h1 = compute_content_hash("Hello World")
+    h2 = compute_content_hash("Hello World!")
+    assert h1 != h2
+
+
+def test_check_content_changed_new_url() -> None:
+    import asyncio
+    import uuid
+
+    unique_url = f"https://example.com/fresh-test-{uuid.uuid4().hex[:8]}"
+    result = asyncio.run(check_content_changed(unique_url, "content"))
+    assert result["is_new"] is True
+    assert result["changed"] is True
+
+
+def test_calculate_frequency_new() -> None:
+    result = calculate_adaptive_frequency("https://example.com", base_interval_minutes=60)
+    assert "suggested_interval_minutes" in result
+    assert result["volatility"] in ("high", "medium", "low")
+
+
+def test_record_and_frequency() -> None:
+    # Record some changes
+    record_check_result("https://example.com/volatile", True)
+    record_check_result("https://example.com/volatile", True)
+    record_check_result("https://example.com/volatile", True)
+    result = calculate_adaptive_frequency("https://example.com/volatile", base_interval_minutes=60)
+    assert result["changes_detected"] >= 3