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>

README.md

@@ -1,12 +1,15 @@
 # PON Fleet Upgrader
 
-An Electron desktop app for bulk operations against a **Ciena
-MicroClimate Management System (MCMS) 6.2** PON Manager. It does two
-things:
+An Electron desktop app for operating a **Ciena MicroClimate Management
+System (MCMS) 6.2** PON Manager. Top tabs split it into:
 
-1. **Bulk ONU firmware upgrades** (below).
-2. **Bulk OLT PON flooding-mode changes** (private↔auto on NNI services —
-   see "OLT PON flooding mode" below).
+1. **Dashboard** — read-only network telemetry: ONU/OLT/controller counts,
+   aggregate up/down traffic, health (abnormal Rx, lasers off), and ONU
+   registration-state breakdown (with an opt-in per-ONU Rx/FEC scan).
+   Clicking a state jumps to the ONU tab pre-filtered.
+2. **ONU** — the fleet table plus **bulk ONU firmware upgrades** (below).
+3. **OLT** — **bulk OLT PON flooding-mode changes** (private↔auto on NNI
+   services — see "OLT PON flooding mode" below).
 
 ## ONU firmware upgrades