fix(config): warn on unknown config keys; delete 7 phantom keys from the example (#146)

* fix(config): warn on unknown config keys instead of silently dropping them

_dict_to_dataclass() silently continue'd past any key not in the target
dataclass's field set -- an operator could set a config key, restart, and
have it vanish with zero feedback (config.example.yaml's phantom
mesh_intelligence keys are exactly this bug, fixed separately).

Now logs a WARNING naming the key and the dataclass, hinting at a typo or
a renamed/removed field, via the module's existing _config_logger.

Traced every dynamic/free-form config path to rule out false positives:
notifications.toggles, notifications.destinations, generic_sources,
mesh_sources, and notifications.rules all route through explicit
dict-of-dataclass or verbatim-passthrough handling and never spuriously
warn. Two legitimate legacy shapes DO hit the strict field-check path with
keys that were never (and will never be) dataclass fields:

- notifications.channels (pre-v0.5 channel list), consumed directly from
  the raw dict by _migrate_legacy_channels
- notifications.region_routes.enabled (pre mt/mc-split master switch),
  read directly by the explicit region_routes handler

Both are allowlisted in _KNOWN_LEGACY_DROP_KEYS so users mid-migration
don't get spurious noise on every load.

Added tests/test_config_loader.py coverage: unknown key warns and does
not raise, both legacy shapes stay silent, and the free-form/dynamic
sections never warn for keys valid on their real target shape.

* fix(config): remove phantom config.example.yaml keys, add missing live ones

The new unknown-key warning (previous commit) caught config.example.yaml
loading with SEVEN warnings, all real drift -- none were false positives
of the warning itself:

mesh_intelligence block shipped three keys with no MeshIntelligenceConfig
field and no implementation anywhere (git log -S confirms they were never
built, not leftovers from a removal):
  - region_radius_miles, infra_overrides, region_labels
These only made sense under an older auto-clustering design; what
actually exists is explicit region anchors (regions: list[RegionAnchor]).
Deleted from both the live block and the commented-out example above it,
and added the four fields that DO exist and are live but were missing
from the example: regions, critical_nodes, alert_channel, alert_rules.

Also fixed the now-misleading comment at
dashboard/api/mesh_routes.py:281, which referenced region_labels --
comment only, no code change.

notifications block shipped a whole quiet-hours subsystem that was
deliberately ripped out (commit b948ed77, "silent is better than ugly")
and never implemented as override_quiet -- confirmed by zero readers and
zero dataclass fields anywhere in meshai/:
  - quiet_hours_enabled, quiet_hours_start, quiet_hours_end
  - override_quiet (on 4 rule entries, including "Emergency Broadcast",
    which falsely implied emergency alerts bypass quiet hours)
Deleted; no quiet-hours feature implemented (out of scope -- product
decision for the owner).

config.example.yaml now loads with exactly zero warnings: the loader and
the example finally agree.

---------

Co-authored-by: Matt Johnson <mj@k7zvx.com>

work/tests/test_config_loader.py

@@ -6,10 +6,14 @@ cfg.notifications.rules as raw dicts (which crashed Dispatcher._matching_rules
 on rule.enabled). config_loader.load_config uses this same _dict_to_dataclass.
 """
 
+import logging
+
 from meshai.config import (
     Config,
+    MeshIntelligenceConfig,
     NotificationRuleConfig,
     NotificationToggle,
+    RegionRouteMatrix,
     _dataclass_to_dict,
     _dict_to_dataclass,
 )
@@ -84,3 +88,88 @@ def test_toggle_meshcore_channel_name_round_trips():
     # Default stays None when unset.
     default = _dict_to_dataclass(NotificationToggle, {"name": "weather"})
     assert default.meshcore_channel is None
+
+
+def test_unknown_key_warns_but_does_not_raise(caplog):
+    """An unrecognized config key (typo, or a renamed/removed field) logs a
+    WARNING naming the key and the dataclass, and the key is silently dropped
+    (never raises). Regression guard for the silent-drop bug: previously an
+    operator could set a bogus/typo'd key, restart, and get zero feedback."""
+    data = {
+        "mesh_intelligence": {
+            "enabled": True,
+            "region_radius_miles": 40.0,  # never a real field -- see config.example.yaml fix
+        }
+    }
+    with caplog.at_level(logging.WARNING, logger="meshai.config"):
+        cfg = _dict_to_dataclass(Config, data)
+
+    assert cfg.mesh_intelligence.enabled is True
+    assert not hasattr(cfg.mesh_intelligence, "region_radius_miles")
+    warnings = [r for r in caplog.records if r.levelno == logging.WARNING]
+    assert len(warnings) == 1
+    msg = warnings[0].getMessage()
+    assert "region_radius_miles" in msg
+    assert "MeshIntelligenceConfig" in msg
+
+
+def test_legacy_region_routes_enabled_does_not_warn(caplog):
+    """region_routes.enabled is a pre-mt/mc-split legacy key, still read
+    directly by the explicit region_routes handler in _dict_to_dataclass.
+    It intentionally has no RegionRouteMatrix field and must NOT warn --
+    warning here would be a false positive for every config still using the
+    pre-split single master switch."""
+    data = {"notifications": {"region_routes": {"enabled": True, "cells": {}}}}
+    with caplog.at_level(logging.WARNING, logger="meshai.config"):
+        cfg = _dict_to_dataclass(Config, data)
+
+    assert cfg.notifications.region_routes.mt_enabled is True
+    assert not any(
+        "region_routes" in r.getMessage() or "'enabled'" in r.getMessage()
+        for r in caplog.records
+    )
+
+
+def test_legacy_notifications_channels_does_not_warn(caplog):
+    """notifications.channels (pre-v0.5 format) has no NotificationsConfig
+    field -- it's consumed directly from the raw dict by
+    _migrate_legacy_channels. Must not warn for users mid-migration."""
+    data = {
+        "notifications": {
+            "channels": [{"id": "c1", "type": "mesh_broadcast", "channel_index": 0}],
+            "rules": [{"name": "r1", "channel_ids": ["c1"], "categories": ["fire"]}],
+        }
+    }
+    with caplog.at_level(logging.WARNING, logger="meshai.config"):
+        cfg = _dict_to_dataclass(Config, data)
+
+    assert len(cfg.notifications.rules) == 1
+    assert cfg.notifications.rules[0].broadcast_channel == 0
+    assert not any("channels" in r.getMessage() for r in caplog.records)
+
+
+def test_dynamic_sections_do_not_warn(caplog):
+    """Sections that are intentionally free-form/passthrough (generic_sources)
+    or use explicit dict-of-dataclass coercion (toggles, destinations) must
+    never warn for keys that ARE valid on their actual target shape."""
+    data = {
+        "notifications": {
+            "toggles": {
+                "weather": {"name": "weather", "enabled": True, "min_severity": "priority"},
+            },
+            "destinations": {
+                "d1": {"name": "d1", "type": "mesh_broadcast", "broadcast_channel": 0},
+            },
+        },
+        "mesh_sources": [
+            {"name": "mv", "type": "meshview", "url": "http://x", "enabled": True},
+        ],
+        "generic_sources": [
+            {"name": "gs1", "enabled": True, "url": "http://x", "not_a_dataclass_field": "fine"},
+        ],
+    }
+    with caplog.at_level(logging.WARNING, logger="meshai.config"):
+        cfg = _dict_to_dataclass(Config, data)
+
+    assert caplog.records == []
+    assert cfg.generic_sources[0]["not_a_dataclass_field"] == "fine"