Add top tabs + telemetry Dashboard + animated edge glow

Restructure the UI behind top-level tabs (Dashboard / ONU / OLT) so more
features have room to land. showView() now drives the active tab via a
VIEW_TO_TAB map, so sub-views (campaign/verify) keep the ONU tab lit.
Tabs appear on login (landing on Dashboard) and hide on logout.

Dashboard: a read-only network telemetry view modeled on the PONGo iOS
app's DashboardViewModel. New api:dashboardStats aggregates, all in
main.js (renderer just formats):
- counts: ONUs, OLTs, controllers (controllers best-effort via
  /v3/controllers/configs/)
- aggregate traffic (OLT TX BW = downstream, RX BW = upstream)
- health: OLTs with laser off; abnormal-Rx count (rx < -28 || > -10)
- ONU registration-state breakdown (clicking a state deep-links to the
  ONU tab pre-filtered)
- opt-in detailed scan: per-ONU optical + FEC-health distribution
fmtBps is a port of the iOS Format.bps.

Edge glow: #edge-glow draws a neon conic-gradient beam masked to a 3px
border ring and spins an @property --beam-angle 0->360deg, so a glow
travels around the screen edge. Honors prefers-reduced-motion.

mcms-api: add listAllControllerConfigs.
Docs: CLAUDE.md section 15 + README + IPC table.

Verified: npm run check passes; rendered the Dashboard + tabs + edge beam
offscreen (beam frozen on the right edge to confirm it follows the border).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

preload.js

@@ -26,6 +26,8 @@ contextBridge.exposeInMainWorld('api', {
 
   deleteOnus: (opts) => call('api:deleteOnus', opts),
 
+  dashboardStats: (opts) => call('api:dashboardStats', opts),
+
   listOlts: (opts) => call('api:listOlts', opts),
   executeFloodChange: (opts) => call('api:executeFloodChange', opts),