Phase 1: public market + universe lookups via ESI

Add a thin async ESI client (httpx, descriptive User-Agent, uniform errors,
mockable transport) plus name<->id resolution. New read-only tools:

- universe: resolve_names, get_item, get_system, get_station, get_region, get_route
- market:   list_hubs, get_market_price, get_market_orders, compare_hubs

Trade-hub IDs (Jita/Amarr/Dodixie/Rens/Hek) are hardcoded constants. Market
aggregation (best buy/sell, spread, order book) lives in pure helpers. 30 unit
tests with mocked ESI; coverage 99%. SDE bulk-load deferred to a later phase.

Closes #2

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/test_universe.py

@@ -0,0 +1,106 @@
+"""Universe lookup tools."""
+
+import asyncio
+
+import httpx
+
+from familiar import universe
+from familiar.server import mcp
+from conftest import route
+
+
+def test_get_item_resolves_name_then_fetches_type(mock_esi):
+    fixtures = {
+        "/universe/ids/": {"inventory_types": [{"id": 34, "name": "Tritanium"}]},
+        "/universe/types/": {
+            "type_id": 34,
+            "name": "Tritanium",
+            "group_id": 18,
+            "volume": 0.01,
+            "packaged_volume": 0.01,
+            "description": "The most common ore type.",
+        },
+    }
+    mock_esi(lambda req: route(req, fixtures))
+    result = asyncio.run(universe.get_item("Tritanium"))
+    assert result["type_id"] == 34
+    assert result["name"] == "Tritanium"
+    assert result["volume"] == 0.01
+
+
+def test_get_system_rounds_security_and_counts(mock_esi):
+    fixtures = {
+        "/universe/systems/": {
+            "system_id": 30000142,
+            "name": "Jita",
+            "constellation_id": 20000020,
+            "security_status": 0.945913,
+            "security_class": "D",
+            "planets": [{}, {}, {}],
+            "stargates": [1, 2],
+        },
+    }
+    mock_esi(lambda req: route(req, fixtures))
+    result = asyncio.run(universe.get_system(30000142))
+    assert result["security_status"] == 0.95
+    assert result["planets"] == 3
+    assert result["stargates"] == 2
+
+
+def test_get_station(mock_esi):
+    fixtures = {
+        "/universe/stations/": {
+            "station_id": 60003760,
+            "name": "Jita IV - Moon 4 - Caldari Navy Assembly Plant",
+            "system_id": 30000142,
+            "type_id": 52678,
+            "services": ["market", "repair-facilities"],
+        },
+    }
+    mock_esi(lambda req: route(req, fixtures))
+    result = asyncio.run(universe.get_station(60003760))
+    assert result["system_id"] == 30000142
+    assert "market" in result["services"]
+
+
+def test_get_region(mock_esi):
+    fixtures = {
+        "/universe/regions/": {
+            "region_id": 10000002,
+            "name": "The Forge",
+            "constellations": [1, 2, 3, 4],
+            "description": "A region.",
+        },
+    }
+    mock_esi(lambda req: route(req, fixtures))
+    result = asyncio.run(universe.get_region(10000002))
+    assert result["name"] == "The Forge"
+    assert result["constellations"] == 4
+
+
+def test_get_route_counts_jumps(mock_esi):
+    fixtures = {"/route/": [30000142, 30000144, 30002187]}
+    mock_esi(lambda req: route(req, fixtures))
+    result = asyncio.run(universe.get_route(30000142, 30002187, prefer="secure"))
+    assert result["jumps"] == 2
+    assert result["flag"] == "secure"
+
+
+def test_get_route_rejects_unknown_flag(mock_esi):
+    fixtures = {"/route/": [30000142]}
+    mock_esi(lambda req: route(req, fixtures))
+    result = asyncio.run(universe.get_route(30000142, 30000142, prefer="banana"))
+    assert result["flag"] == "shortest"
+    assert result["jumps"] == 0
+
+
+def test_resolve_names_passthrough(mock_esi):
+    body = {"systems": [{"id": 30000142, "name": "Jita"}]}
+    mock_esi(lambda req: httpx.Response(200, json=body))
+    result = asyncio.run(universe.resolve_names(["Jita"]))
+    assert result["systems"][0]["id"] == 30000142
+
+
+def test_universe_tools_are_registered():
+    tools = {t.name for t in asyncio.run(mcp.list_tools())}
+    assert {"get_item", "get_system", "get_station", "get_region", "get_route"} <= tools