merge: reconcile PR 40 with current lab

Integrate lab fff55a78 into PR #40 (cc25d5ba). Lab's modular email
backend/frontend, modular settings, split stylesheets (static/style.css
stays deleted), procfs compatibility, and request-scoped TurnContract
authority win; PR #40's routing classifiers, editor/email/task features,
and style.css changes are ported into lab's module and stylesheet homes.

Integration fixes:
- settings/api.js imports ui.js under its canonical versioned URL
- browser observations keep legacy CAPTCHA/access-block evidence
- artifact turns do not re-trigger broad-web research recovery
- env reference documents PR test-tool variables; page regenerated

PR #40 defects surfaced by lab gates and fixed here:
- web_fetch generic schema drops top-level anyOf (OpenAI contract);
  the compact preview contract still requires url or urls
- get_weather registered as a brokered network read
- new lazy editor modules precached for offline use
- SearXNG pin mirrored into GPU standalone compose files
- image model picker again skips offline endpoints

Tests updated where PR #40 changed behaviour on purpose, and PR tests
moved onto lab's document_source helpers.

tests/test_chat_ttft_timer_static.py

@@ -25,10 +25,11 @@ def test_measured_ttft_is_shown_in_message_stats():
 
 def test_compact_footer_and_details_show_real_performance_counters():
     assert "`${Number(tps).toFixed(2)} tok/s`" in RENDERER
-    assert "`${Number(ttft).toFixed(3)}s TTFT`" in RENDERER
-    assert "`${Number(injectedTokens).toLocaleString()} in`" in RENDERER
+    assert "const visibleTtft = metrics.client_ttft ?? metrics.time_to_first_token" in RENDERER
+    assert "${Number(visibleTtft).toFixed(3)}s" in RENDERER
     assert '<span class="ctx-label">Input</span>' in RENDERER
-    assert '<span class="ctx-label">Injected</span>' in RENDERER
+    # Injected-context size is no longer a separate details row.
+    assert '<span class="ctx-label">Injected</span>' not in RENDERER
     assert 'all rounds' not in RENDERER
     assert 'first request' not in RENDERER
     assert 'Tool schemas' in RENDERER