fix(plugin-manager): fix TypeError breaking every plugin's scheduled update (#392)

run_scheduled_updates()'s resource-monitor branch wrapped the update call
in a closure stored as a *class* attribute on a dynamically-built type
(type('obj', (object,), {'update': monitored_update})()). The descriptor
protocol turns a function found via class-attribute lookup into a bound
method on instance access, silently prepending the synthetic instance as
an implicit first argument -- but monitored_update() takes none, so every
call raised "monitored_update() takes 0 positional arguments but 1 was
given", was caught by run_scheduled_updates' try/except, and recorded as
an update failure.

self.resource_monitor is None by default and was dormant until PR #388
("activate dormant plugin health/metrics subsystem") wired it up in both
display_controller.py and web_interface/app.py -- meaning this bug went
live in every real deployment as of that merge (2026-07-09) despite the
buggy line itself dating back to 2025-12-27. In practice this means no
plugin's update() has succeeded since upgrading past #388: circuit
breakers cycle through half-open -> immediate failure -> reopened every
health-check interval forever, and all plugin data (scores, odds, prices,
etc.) goes stale from whatever was last fetched before the upgrade.
Confirmed live on a running instance: odds-ticker (and stock-news,
ledmatrix-stocks, baseball-scoreboard, ledmatrix-leaderboard, of-the-day)
failing this exact way every 5-minute circuit-breaker retry.

Fixed by using types.SimpleNamespace(update=monitored_update) instead of
a dynamic class: SimpleNamespace stores attributes on the instance
itself, so attribute lookup returns the plain function unchanged --
never routed through the class-attribute descriptor protocol that
injects an implicit self.

Added test_run_scheduled_updates_calls_update_with_resource_monitor to
test/test_plugin_system.py using a real PluginResourceMonitor (not a
mock of it), so the test exercises the actual descriptor-binding
behavior that caused this. Verified the test fails with the exact
reported error against the pre-fix code and passes against the fix.

src/plugin_system/plugin_manager.py

@@ -12,6 +12,7 @@ import sys
 import subprocess
 import time
 import threading
+import types
 from pathlib import Path
 from typing import Dict, List, Optional, Any
 import logging
@@ -828,8 +829,18 @@ class PluginManager:
                         # If resource monitor exists, wrap the call
                         def monitored_update():
                             self.resource_monitor.monitor_call(plugin_id, plugin_instance.update)
+                        # SimpleNamespace stores `update` as an *instance*
+                        # attribute, so attribute lookup returns the plain
+                        # function object as-is. A dynamically-built class
+                        # (`type(..., {'update': monitored_update})`) instead
+                        # stores it as a *class* attribute, which the
+                        # descriptor protocol turns into a bound method on
+                        # access -- silently prepending the instance as an
+                        # implicit first argument to a function that takes
+                        # none, raising "monitored_update() takes 0
+                        # positional arguments but 1 was given" on every call.
                         success = self.plugin_executor.execute_update(
-                            type('obj', (object,), {'update': monitored_update})(),
+                            types.SimpleNamespace(update=monitored_update),
                             plugin_id
                         )
                     else: