Apply LotusGuild design system convergence (aesthetic_diff.md)

CSS (style.css):
- §1: Add unified naming aliases (--terminal-green, --bg-primary, etc.)
- §2: Upgrade borders: modal 1px→3px double, btn/btn-sm/inputs 1px→2px
- §3: Add [ ] bracket decorations to .btn classes; primary keeps > prefix;
  hover lift -1px→-2px; padding 6px 14px→5px 12px
- §4: Fix glow definitions from 2-layer rgba to 3-layer solid stack
- §5: Section headers now symmetric ╠═══ TITLE ═══╣ (was one-sided)
- §6+§7: Modal border 3px double, corners ┌┐→╔╗, add glow shadow
- §11: Nav active state now amber tint (was green); hover remains green
- §15: Scanline opacity 0.13→0.15; flicker delay 45s→30s

JS (app.js):
- §18: Replace custom showToast() with lt.toast.* delegate wrapper

Templates (base.html):
- Load base.css and base.js (symlinked from web_template)
- Add lt-boot overlay for boot sequence animation (§13)

README: Remove completed pending convergence items

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

README.md

@@ -5,6 +5,19 @@
 Network monitoring dashboard for the LotusGuild Proxmox cluster.
 Deployed on **LXC 157** (monitor-02 / 10.10.10.9), reachable at `gandalf.lotusguild.org`.
 
+**Design System**: [web_template](https://code.lotusguild.org/LotusGuild/web_template) — shared CSS, JS, and layout patterns for all LotusGuild apps
+
+## Styling & Layout
+
+GANDALF uses the **LotusGuild Terminal Design System**. For all styling, component, and layout documentation see:
+
+- [`web_template/README.md`](https://code.lotusguild.org/LotusGuild/web_template/src/branch/main/README.md) — full component reference, CSS variables, JS API
+- [`web_template/base.css`](https://code.lotusguild.org/LotusGuild/web_template/src/branch/main/base.css) — unified CSS (`.lt-*` classes)
+- [`web_template/base.js`](https://code.lotusguild.org/LotusGuild/web_template/src/branch/main/base.js) — `window.lt` utilities (toast, modal, auto-refresh, fetch helpers)
+- [`web_template/aesthetic_diff.md`](https://code.lotusguild.org/LotusGuild/web_template/src/branch/main/aesthetic_diff.md) — cross-app divergence analysis and convergence guide
+- [`web_template/python/base.html`](https://code.lotusguild.org/LotusGuild/web_template/src/branch/main/python/base.html) — Jinja2 base template
+- [`web_template/python/auth.py`](https://code.lotusguild.org/LotusGuild/web_template/src/branch/main/python/auth.py) — `@require_auth` decorator pattern
+
 ---
 
 ## Architecture