config: agent_panel block (enabled/surfaces/min_quality/daily budget)

New optional config.json block for the upcoming LLM agent-panel feature:
enabled, telegram, dashboard (per-surface toggles), min_quality,
max_panels_per_day, reuse_ttl_seconds. Absent block → {} → feature dark.
Validation mirrors the deepseek block. Module 23 opened with parse +
reject tests.

Claude-Session: https://claude.ai/code/session_01SisdfkxnXNL9iZsXxN3T15

test_all.py

@@ -6943,6 +6943,42 @@ def _():
         assert "must be > 0" in str(e)
 
 
+print("\n═══ Module 23: LLM agent panel ═══")
+
+
+@test("app_config: agent_panel block parses; absent block → {}")
+def _():
+    app = load_app_config(_write_json({"agent_panel": {
+        "enabled": True, "telegram": True, "dashboard": False,
+        "min_quality": "A", "max_panels_per_day": 10,
+        "reuse_ttl_seconds": 600}}))
+    assert app.agent_panel_settings["enabled"] is True
+    assert app.agent_panel_settings["min_quality"] == "A"
+    assert app.agent_panel_settings["max_panels_per_day"] == 10
+    assert load_app_config(_write_json({})).agent_panel_settings == {}
+    assert AppConfig().agent_panel_settings == {}
+
+
+@test("app_config: agent_panel rejects unknown keys and bad types")
+def _():
+    for payload in (
+        {"agent_panel": {"enabld": True}},               # unknown key
+        {"agent_panel": {"enabled": "yes"}},             # not a bool
+        {"agent_panel": {"telegram": 1}},                # not a bool
+        {"agent_panel": {"dashboard": "no"}},            # not a bool
+        {"agent_panel": {"min_quality": "Z"}},           # invalid grade
+        {"agent_panel": {"max_panels_per_day": 0}},      # not positive
+        {"agent_panel": {"max_panels_per_day": True}},   # bool is not an int
+        {"agent_panel": {"reuse_ttl_seconds": -5}},      # negative
+        {"agent_panel": "oops"},                         # not an object
+    ):
+        try:
+            load_app_config(_write_json(payload))
+            assert False, f"should have raised for {payload}"
+        except AppConfigError:
+            pass
+
+
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