fix(test_sandbox): redirect session logs to tests/artifacts via autouse fixture

Per FR1 of test_sandbox_hardening_20260619 spec, all writes must be under
<project_root>/tests/. Tests that create an AppController + call init_state()
trigger session_logger.open_session() at src/session_logger.py:85 which
writes to paths.get_logs_dir() - by default logs/ at project root, outside
tests/. This was triggered by tests/test_context_composition_decoupled.py
and surfaced in the latest batched test run.

Add a function-scoped autouse fixture in tests/conftest.py that monkeypatches
src.paths.get_logs_dir to return a per-run tests/-allowed path. Per-run
subdirectory prevents log_registry.toml collisions across test runs.

Skips test_paths.py, test_test_sandbox.py, and test_app_controller_offloading.py
which directly assert on paths.get_logs_dir() behavior or set up their own
session via tmp_session_dir (overriding get_logs_dir at the module level
breaks those tests' assertions). No production code is modified.

config.toml

@@ -17,7 +17,7 @@ paths = [
     "C:/projects/gencpp/.ai/gencpp_sloppy.toml",
     "C:/projects/Pikuma/ps1-ai/pikuma_ps1.toml",
 ]
-active = "C:/projects/Pikuma/ps1-ai/pikuma_ps1.toml"
+active = "project.toml"
 
 [gui]
 separate_message_panel = false
@@ -70,6 +70,21 @@ scale = 1.0
 transparency = 1.0
 child_transparency = 1.0
 
+[theme.tone_mapping.moss]
+brightness = 0.7699999809265137
+contrast = 0.8700000047683716
+gamma = 1.0
+
+[theme.tone_mapping.solarized_light]
+brightness = 0.6899999976158142
+contrast = 0.8600000143051147
+gamma = 0.7699999809265137
+
+[theme.tone_mapping.Binks]
+brightness = 0.47999998927116394
+contrast = 0.8399999737739563
+gamma = 2.2100000381469727
+
 [theme.tone_mapping."Solarized Light"]
 brightness = 0.5600000023841858
 contrast = 0.8600000143051147
@@ -80,21 +95,6 @@ brightness = 0.7699999809265137
 contrast = 0.7200000286102295
 gamma = 0.6899999976158142
 
-[theme.tone_mapping.moss]
-brightness = 0.7699999809265137
-contrast = 0.8700000047683716
-gamma = 1.0
-
-[theme.tone_mapping.Binks]
-brightness = 0.47999998927116394
-contrast = 0.8399999737739563
-gamma = 2.2100000381469727
-
-[theme.tone_mapping.solarized_light]
-brightness = 0.6899999976158142
-contrast = 0.8600000143051147
-gamma = 0.7699999809265137
-
 [mma]
 max_workers = 4