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_document_edit_reference_js.py

@@ -1,12 +1,14 @@
 """Regression guards for document-selection references in chat bubbles."""
 
 from pathlib import Path
+from tests.helpers.stylesheets import app_css
+from tests.helpers.document_source import document_source, function_body
 
 
 ROOT = Path(__file__).resolve().parents[1]
 RENDERER = (ROOT / "static/js/chatRenderer.js").read_text(encoding="utf-8")
-DOCUMENT = (ROOT / "static/js/document.js").read_text(encoding="utf-8")
-STYLE = (ROOT / "static/style.css").read_text(encoding="utf-8")
+DOCUMENT = document_source()
+STYLE = app_css()
 INDEX = (ROOT / "static/index.html").read_text(encoding="utf-8")
 APP = (ROOT / "static/app.js").read_text(encoding="utf-8")
 
@@ -46,7 +48,7 @@ def test_document_module_has_one_browser_identity_for_restore_and_chat_send():
 
 
 def test_clearing_a_rich_selection_also_resets_native_selection_stats():
-    clear_body = DOCUMENT.split("function clearSelection() {", 1)[1].split("\n  }", 1)[0]
+    clear_body = function_body("clearSelection")
 
     assert "browserSelection.removeAllRanges()" in clear_body
     assert "_scheduleDocumentStats()" in clear_body