Add overview repo and verae-nats-process expansion template

High-level system map with diagrams, TOC, and a docs index. Template
worker shows how to add a new verae.* address for search, storage, or
unplanned functions without teaching Zapier NATS.

scripts/build-docs-site.py

@@ -33,6 +33,8 @@ SECTIONS = [
             ("docs/02-architecture/modules-and-nats.md", "Module catalog and NATS addresses"),
             ("docs/02-architecture/tree-nodes.md", "Tree nodes and bulk Merkle summaries"),
             ("docs/02-architecture/fleet.md", "Fleet replica floors and monitor"),
+            ("packages/overview/README.md", "System overview (TOC)"),
+            ("packages/overview/INDEX.md", "Documentation index"),
         ],
     ),
     (
@@ -141,6 +143,8 @@ def main() -> None:
         "verae-zapier-simulator",
         "zapier-user-docs",
         "verae-fleet",
+        "overview",
+        "verae-nats-process",
         "docs-master",
     ):
         readme = ROOT / "packages" / pkg / "README.md"
@@ -157,6 +161,7 @@ def main() -> None:
             copy_tree(src, SITE / src.name if src.parent == ROOT else SITE / "docs" / "OPEN.md")
     copy_tree(ROOT / "docs" / "WORK-LOG.md", SITE / "docs" / "WORK-LOG.md")
     copy_tree(ROOT / "packages" / "docs-master", SITE / "docs-master")
+    copy_tree(ROOT / "packages" / "overview", SITE / "overview")
     copy_tree(ROOT / "packages" / "zapier-user-docs", SITE / "user-docs", ignore=shutil.ignore_patterns("node_modules"))
     sim_pub = ROOT / "packages" / "verae-zapier-simulator" / "public" / "index.html"
     if sim_pub.exists():
@@ -235,6 +240,8 @@ def main() -> None:
         ("verae-zapier-simulator", "Zapier interface + trace console"),
         ("zapier-user-docs", "Signup-to-usage user guide"),
         ("verae-fleet", "Service catalog, replica floors, monitor"),
+        ("overview", "High-level system overview"),
+        ("verae-nats-process", "Template for a new NATS address"),
     ]
     git_lis = "".join(
         f'<li><a href="https://git.georgelambert.org/marchon/{name}">{name}</a> '
@@ -292,6 +299,9 @@ def main() -> None:
       <li><a href="docs-master/modules/">Per-module SUMMARY.md and NATS.md</a></li>
       <li><a href="user-docs/README.md">User guide (signup → tree-node lookup)</a></li>
       <li><a href="packages/verae-zapier-simulator/README.md">Simulator README</a></li>
+      <li><a href="overview/README.md">System overview</a></li>
+      <li><a href="overview/INDEX.md">Documentation index</a></li>
+      <li><a href="overview/diagrams/system.svg">System diagram (SVG)</a></li>
     </ul>
   </section>
   <section>