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_preview_drafting_recovery.py

@@ -19,10 +19,14 @@ def test_explicit_thinking_off_wins_without_tools(monkeypatch):
 
 def test_fetch_requires_a_page_in_full_and_compact_contracts():
     schema = next(s for s in FUNCTION_TOOL_SCHEMAS if s['function']['name'] == 'web_fetch')
-    for item in [schema, compact_schemas([schema])[0]]:
-        params = item['function']['parameters']
-        with pytest.raises(jsonschema.ValidationError):
-            jsonschema.validate({'query': 'compose a letter'}, params)
+    # The preview validates calls against the compact contract, which requires
+    # url or urls. The full schema is sent to providers whose top-level
+    # parameter contract rejects anyOf (test_model_tool_modes), so it accepts
+    # both forms without the combinator.
+    compact = compact_schemas([schema])[0]['function']['parameters']
+    with pytest.raises(jsonschema.ValidationError):
+        jsonschema.validate({'query': 'compose a letter'}, compact)
+    for params in [schema['function']['parameters'], compact]:
         jsonschema.validate({'url': 'https://example.com', 'query': 'details'}, params)
         jsonschema.validate({'urls': ['https://example.com']}, params)