Feat v0.7.4 documentation + deferred surface work

Docs restructuring: category grouping (Getting Started, Platform,
Extension Development, Operations) with 14 ordered docs. Four new
guides: Permissions & Groups, Workflows, Starlark Reference, Frontend
JS Guide. Extension Guide updated with config_section docs.

Content refresh across 10 existing docs: rebrand volume names,
stale CSS vars, TLS_MODE env, self-hosted font notes, Architecture
frontend section.

Team Admin workflows.js (722 lines) split into 3 modules:
workflows.js (router+CRUD), workflow-editor.js (editor+stages),
workflow-monitor.js (assignments+monitor+signoff).

Fix: docs outline scroll no longer pushes topbar off-screen.
Fix: --bg-2 (undefined CSS var) replaced with --bg-secondary.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/ARCHITECTURE.md

@@ -271,12 +271,13 @@ graph TD
 ## Frontend
 
 Preact (3KB) + htm (tagged template literals). No build step, no bundler
-(except CM6 via esbuild). IIFE/global-namespace pattern with
-`sb.register()`/`sb.ns()`.
+(except CM6 via esbuild). ES modules loaded via `<script type="module">`.
+The SDK is exposed at `window.sw` — see the [Frontend JS Guide](FRONTEND-JS-GUIDE).
 
-The shell loads surfaces into a viewport. Extensions use `window.html`
-and `window.preact` directly. Hooks via `window.hooks`. Vendor libs
-(marked.js, DOMPurify, KaTeX, CodeMirror 6) baked into the image.
+The shell provides a two-slot topbar (left title + center slot) that every
+surface inherits. Extensions use `window.html` and `window.preact` directly.
+Hooks via `window.hooks`. Vendor libs (marked.js, DOMPurify, KaTeX,
+CodeMirror 6) baked into the image.
 
 ## Deployment