feat: sync with upstream — v1.2.0, in-app updates, Projects, modules

Brings the public tree back in line with the development repo after several
weeks of drift caused by a stale publish include list.

New:
- In-app update path: GET /update/check compares the checkout against
  origin/main and POST /update/apply runs `ncp upgrade` detached (pull,
  rebuild, restart). The sidebar shows the version, checks on click, and
  offers an "update available" pill.
- Projects: a project workspace groups chats and RAG documents, with
  per-project instructions and document retrieval scoped to the active
  project. Replaces the standalone Documents page.
- modules/: auto-discovered feature plugins (mail, network) with their
  frontend counterparts and tests.
- Memory curation runs in-process (synapse/memory/curator.py) on the chat
  model when a conversation goes idle. The separate memory service on :8001
  is gone, along with the launcher lines that started it.

Also: the KDE theme, panel and Promethean terminal assets, the full test
suite, and VERSION 1.2.0.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

bin/backup-linux.sh

@@ -51,6 +51,18 @@ if [ -d "$HOME/.config/plank" ]; then
     mkdir -p "$snap/plank"
     cp -rf "$HOME/.config/plank/." "$snap/plank/" 2>/dev/null || true
 fi
+# The .dockitem files alone are NOT the dock. Everything else — item list, theme,
+# icon size, position, hide mode — lives in dconf, and on startup Plank DELETES
+# every .dockitem not in its list, so copying files alone restores nothing.
+# `monitor` is stripped: it's per-machine, and plank-primary-watch.sh sets it.
+dconf dump /net/launchpad/plank/ 2>/dev/null | grep -v '^monitor=' > "$snap/plank-dconf.ini" || true
+# Dock launchers point at .desktop files in ~/.local/share/applications, which
+# is outside the repo — Plank prunes any item whose target is missing.
+mkdir -p "$snap/applications"
+for d in $(sed -n 's#.*applications/\([^.]*\.desktop\).*#\1#p' \
+           "$snap"/plank/dock1/launchers/*.dockitem 2>/dev/null); do
+    cp -f "$HOME/.local/share/applications/$d" "$snap/applications/$d" 2>/dev/null || true
+done
 
 # Copy the Claude memory notes (machine knowledge under ~/.claude) into the
 # repo so they're versioned too. Some aren't Nexus-specific (Fusion 360, etc.).