docs: restructure website, optimize HTML, gitignore private files

Website docs (website/docs/):
- Delete 6 stale -md.html duplicates
- Rename docs-clients/miners/developers → clients/miners/developers.html
- Unify header/nav across all 15 pages (new .site-header pattern)
- Fix 34 dead href=# links with real targets
- Upgrade Font Awesome v4→v6 in index.html
- Replace search stub with live client-side search (15-page index)
- Extract all inline CSS into shared docs.css (+630 lines)
- Extract inline theme JS into shared theme.js
- Strip inline style= attributes from 10+ pages
- Add .announce-banner, .source-links, .search-results CSS classes
- Add Markdown Source links to clients/miners/developers pages
- Update components.html title to Architecture & Components
- Move browser-wallet.html to website/wallet/, leave redirect
- Update all dates to February 2026

Website root:
- Delete 6 root-level duplicate HTML files (160KB saved)
- Rewire index.html and 404.html links

Root README.md:
- Fix 8 broken doc links to new numbered folder structure
- Update copyright to 2026

.gitignore + .example files:
- Gitignore private files: .aitbc.yaml, .env, deploy scripts,
  GPU scripts, service scripts, infra configs, .windsurf/, website README
- Create 7 .example files for GitHub users with sanitized templates
- Untrack 47 previously committed private files

Live server:
- Push all website files to aitbc-cascade:/var/www/html/
- Clean stale admin.html and index.nginx-debian.html

scripts/deploy/deploy-to-aitbc-container.sh

@@ -1,84 +0,0 @@
-#!/bin/bash
-
-# Deploy blockchain node inside incus container aitbc
-
-set -e
-
-echo "🚀 AITBC Deployment in Incus Container"
-echo "======================================"
-echo "This will deploy inside the aitbc container"
-echo ""
-
-# Colors
-GREEN='\033[0;32m'
-YELLOW='\033[1;33m'
-NC='\033[0m'
-
-print_status() {
-    echo -e "${GREEN}[INFO]${NC} $1"
-}
-
-print_warning() {
-    echo -e "${YELLOW}[WARN]${NC} $1"
-}
-
-# Check if we're on ns3 host
-if [ "$(hostname)" != "ns3" ]; then
-    print_warning "This script must be run on ns3 host"
-    echo "Run: ssh ns3-root"
-    exit 1
-fi
-
-# Check if container exists
-if ! incus list | grep -q "aitbc.*RUNNING"; then
-    print_warning "Container aitbc is not running"
-    exit 1
-fi
-
-# Copy source to container
-print_status "Copying source code to container..."
-incus exec aitbc -- rm -rf /opt/blockchain-node-src 2>/dev/null || true
-incus exec aitbc -- mkdir -p /opt/blockchain-node-src
-# Use the source already on the server
-incus file push -r /opt/blockchain-node-src/. aitbc/opt/blockchain-node-src/
-# Fix the nested directory issue - move everything up one level
-incus exec aitbc -- sh -c 'if [ -d /opt/blockchain-node-src/blockchain-node-src ]; then mv /opt/blockchain-node-src/blockchain-node-src/* /opt/blockchain-node-src/ && rmdir /opt/blockchain-node-src/blockchain-node-src; fi'
-
-# Copy deployment script to container
-print_status "Copying deployment script to container..."
-incus file push /opt/deploy-in-container.sh aitbc/opt/
-
-# Execute deployment inside container
-print_status "Deploying inside container..."
-incus exec aitbc -- bash /opt/deploy-in-container.sh
-
-# Setup port forwarding on host
-print_status "Setting up port forwarding on host..."
-iptables -t nat -F PREROUTING 2>/dev/null || true
-iptables -t nat -F POSTROUTING 2>/dev/null || true
-
-# Forward blockchain RPC
-iptables -t nat -A PREROUTING -p tcp --dport 8082 -j DNAT --to-destination 192.168.100.10:8082
-iptables -t nat -A POSTROUTING -p tcp -d 192.168.100.10 --dport 8082 -j MASQUERADE
-
-# Forward explorer
-iptables -t nat -A PREROUTING -p tcp --dport 3000 -j DNAT --to-destination 192.168.100.10:3000
-iptables -t nat -A POSTROUTING -p tcp -d 192.168.100.10 --dport 3000 -j MASQUERADE
-
-# Save rules
-mkdir -p /etc/iptables
-iptables-save > /etc/iptables/rules.v4
-
-# Check services
-print_status "Checking services in container..."
-incus exec aitbc -- systemctl status blockchain-node blockchain-rpc nginx --no-pager | grep -E 'Active:|Main PID:'
-
-print_success "✅ Deployment complete!"
-echo ""
-echo "Services in container aitbc:"
-echo "  - Blockchain Node RPC: http://192.168.100.10:8082"
-echo "  - Blockchain Explorer: http://192.168.100.10:3000"
-echo ""
-echo "External access via ns3:"
-echo "  - Blockchain Node RPC: http://aitbc.keisanki.net:8082"
-echo "  - Blockchain Explorer: http://aitbc.keisanki.net:3000"