chore(deprecation): remove the 35 APIs deprecated for 3.8.0 (#708)

* chore(deprecation): remove the 35 APIs deprecated for 3.8.0

The usage scan (docs/DEPRECATIONS_3.8.md, regenerated 2026-10-01 and
committed here) finds no call or override of any of them in the 46
monorepo plugins or the 8 third-party plugins plugins.json lists; the
only core callers were other deprecated methods removed alongside.

- CacheManager: 13 methods, plus the private helpers only
  has_data_changed used (_has_*_changed, _is_market_open).
- DisplayManager: 7 methods, plus WEATHER_COLORS and the private
  _draw_sun/_cloud/_rain/_snow/_storm helpers only the icon methods used.
- FontManager: 14 methods, plus size_tokens, _save_overrides and
  _clear_plugin_font_cache. font_overrides and _load_overrides stay:
  resolve_font() still applies config/font_overrides.json.
  performance_stats stays: get_font() keeps it and tests read it.
- PluginManager.get_enabled_plugins.

test_deprecation.py pins only the two 3.9.0 markers now; the scanner
tests run against a stand-in core instead of the real markers. The
memory-tier tests read stats through log_memory_cache_stats() and the
component, and the test of the removed _clear_plugin_font_cache goes.
Docs drop the removed methods' reference entries; the Deprecated APIs
table becomes "Removed in 3.8.0". CHANGELOG gains a Removed section.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* chore(deprecation): drop the test harness's copies of the removed icon methods

VisualTestDisplayManager still drew weather icons that DisplayManager no
longer has, so a plugin's visual tests could pass on calls that raise
AttributeError on the real display. Its draw_sun/draw_cloud/draw_rain/
draw_snow/draw_weather_icon/draw_text_with_icons, WEATHER_COLORS and the
private helpers go, with the tests that exercised them. The CHANGELOG's
Deprecations entries no longer say nothing is removed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

test/test_cache_manager_memory_tier.py

@@ -40,11 +40,9 @@ def test_cleanup_and_stats_follow_a_replaced_component(cm):
     assert cm._memory_cache_component.get("stale") is None
     assert cm._memory_cache_component.get("fresh") == {"v": 1}
 
-    stats = cm.get_memory_cache_stats()
-    assert stats["size"] == 1
-    assert stats["max_size"] == 7
-    assert stats["cleanup_interval"] == 11.0
-    assert stats["usage_percent"] == pytest.approx(100 / 7)
+    with patch.object(cm.logger, "info") as info:
+        cm.log_memory_cache_stats()
+    assert "Size: 1/7 (14.3%)" in info.call_args[0][0]
 
 
 def test_periodic_cleanup_is_throttled_and_records_its_run(cm):
@@ -60,16 +58,16 @@ def test_periodic_cleanup_is_throttled_and_records_its_run(cm):
     before = time.time()
     cm.get_cached_data("missing")          # triggers the periodic sweep
     assert mem.size() == 0
-    assert cm.get_memory_cache_stats()["last_cleanup"] >= before
+    assert mem.get_stats()["last_cleanup"] >= before
 
 
-def test_stats_have_the_documented_shape(cm):
+def test_memory_stats_log_reads_the_live_tier(cm):
     cm.set("k", {"v": 1})
-    stats = cm.get_memory_cache_stats()
-    assert set(stats) == {"size", "max_size", "usage_percent",
-                          "last_cleanup", "cleanup_interval"}
-    assert stats["size"] == 1
-    assert stats["max_size"] == cm._memory_cache_component.max_size()
+    with patch.object(cm.logger, "info") as info:
+        cm.log_memory_cache_stats()
+    message = info.call_args[0][0]
+    assert f"Size: 1/{cm._memory_cache_component.max_size()}" in message
+    assert "Last cleanup:" in message
 
 
 def test_listing_the_cache_dir_does_not_hold_the_memory_lock(cm, tmp_path):