feat(egress): add global log option for full request/response logging

Adds a top-level `log: true` option to the egress config that logs the
full request (method, path, headers, body) and response (status, headers,
body) for every forwarded connection as JSON lines on stderr.

Wire format: `log: true` at the root of routes.yaml, parsed into the new
`Config` dataclass alongside `routes`. The sidecar addon switches from
`self.routes` to `self.config` and writes `_log_request` / `_log_response`
JSON lines when `self.config.log` is set.

Manifest: `egress.log: true` in bottle YAML flows through `EgressConfig.Log`
→ `Egress.prepare()` → `egress_render_routes(..., log=)` → routes.yaml.
`EgressPlan` also carries the flag for introspection.

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

tests/unit/test_egress.py

@@ -324,6 +324,44 @@ class TestRenderRoutes(unittest.TestCase):
         self.assertEqual(("token_patterns",), addon_routes[0].outbound_detectors)
         self.assertEqual((), addon_routes[0].inbound_detectors)
 
+    def test_log_false_omitted_from_render(self):
+        b = _bottle([{"host": "x.example"}])
+        routes = egress_routes_for_bottle(b)
+        rendered = egress_render_routes(routes, log=False)
+        self.assertNotIn("log:", rendered)
+
+    def test_log_true_emitted_at_top_level(self):
+        b = _bottle([{"host": "x.example"}])
+        routes = egress_routes_for_bottle(b)
+        rendered = egress_render_routes(routes, log=True)
+        self.assertTrue(rendered.startswith("log: true\n"))
+
+    def test_log_true_round_trips_to_addon_core(self):
+        from bot_bottle.egress_addon_core import load_config
+        b = _bottle([{"host": "x.example"}])
+        routes = egress_routes_for_bottle(b)
+        rendered = egress_render_routes(routes, log=True)
+        cfg = load_config(rendered)
+        self.assertTrue(cfg.log)
+        self.assertEqual("x.example", cfg.routes[0].host)
+
+    def test_log_via_manifest_flows_to_render(self):
+        from bot_bottle.manifest import Manifest
+        from bot_bottle.egress_addon_core import load_config
+        m = Manifest.from_json_obj({
+            "bottles": {"dev": {"egress": {
+                "log": True,
+                "routes": [{"host": "x.example"}],
+            }}},
+            "agents": {"demo": {"skills": [], "prompt": "", "bottle": "dev"}},
+        })
+        bottle = m.bottles["dev"]
+        self.assertTrue(bottle.egress.Log)
+        routes = egress_routes_for_bottle(bottle)
+        rendered = egress_render_routes(routes, log=bottle.egress.Log)
+        cfg = load_config(rendered)
+        self.assertTrue(cfg.log)
+
 
 class TestResolveTokenValues(unittest.TestCase):
     def test_reads_host_env(self):