Docs, README, launchers, PWA install

Milestone 7. docs/MODULE-GUIDE.md documents the whole module contract
from an author's point of view — manifest reference, client factory +
moduleApi, server init/routes/health, scoping and resilience rules, a
copy-paste minimal module, and a testing section with the two mocks and a
resilience checklist. README rewritten with run/configure/use
instructions in the prodcom-listener style, plus double-click launchers
for macOS and Windows. PWA: manifest, icons, and a minimal network-first
service worker that never touches /api/*.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RNYUv9EyrGSFmCnmH7WYKH

public/manifest.webmanifest

@@ -0,0 +1,30 @@
+{
+  "name": "ProdDash",
+  "short_name": "ProdDash",
+  "description": "Modular production dashboard for Waters Church",
+  "start_url": "/",
+  "scope": "/",
+  "display": "standalone",
+  "background_color": "#0b0e12",
+  "theme_color": "#0b0e12",
+  "icons": [
+    {
+      "src": "/icons/icon-192.png",
+      "sizes": "192x192",
+      "type": "image/png",
+      "purpose": "any"
+    },
+    {
+      "src": "/icons/icon-512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "any"
+    },
+    {
+      "src": "/icons/icon-512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "maskable"
+    }
+  ]
+}