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

infra/helm/values/prod.yaml

@@ -1,140 +0,0 @@
-# Production environment values
-global:
-  environment: production
-
-coordinator:
-  replicaCount: 3
-  image:
-    tag: "v0.1.0"
-  resources:
-    limits:
-      cpu: 2000m
-      memory: 2Gi
-    requests:
-      cpu: 1000m
-      memory: 1Gi
-  autoscaling:
-    enabled: true
-    minReplicas: 3
-    maxReplicas: 20
-    targetCPUUtilizationPercentage: 75
-    targetMemoryUtilizationPercentage: 80
-  config:
-    appEnv: production
-    allowOrigins: "https://app.aitbc.io"
-  postgresql:
-    auth:
-      existingSecret: "coordinator-db-secret"
-    primary:
-      persistence:
-        size: 200Gi
-        storageClass: fast-ssd
-      resources:
-        limits:
-          cpu: 2000m
-          memory: 4Gi
-        requests:
-          cpu: 1000m
-          memory: 2Gi
-    readReplicas:
-      replicaCount: 2
-      resources:
-        limits:
-          cpu: 1000m
-          memory: 2Gi
-        requests:
-          cpu: 500m
-          memory: 1Gi
-
-monitoring:
-  prometheus:
-    server:
-      retention: 90d
-      persistentVolume:
-        size: 500Gi
-        storageClass: fast-ssd
-      resources:
-        limits:
-          cpu: 2000m
-          memory: 4Gi
-        requests:
-          cpu: 1000m
-          memory: 2Gi
-  grafana:
-    adminPassword: "prod-admin-secure-2024"
-    persistence:
-      size: 50Gi
-      storageClass: fast-ssd
-    resources:
-      limits:
-        cpu: 1000m
-          memory: 2Gi
-        requests:
-          cpu: 500m
-          memory: 1Gi
-    ingress:
-      enabled: true
-      hosts:
-        - grafana.aitbc.io
-
-# Additional services
-blockchainNode:
-  replicaCount: 5
-  resources:
-    limits:
-      cpu: 2000m
-      memory: 2Gi
-    requests:
-      cpu: 1000m
-      memory: 1Gi
-  autoscaling:
-    enabled: true
-    minReplicas: 5
-    maxReplicas: 50
-    targetCPUUtilizationPercentage: 70
-
-walletDaemon:
-  replicaCount: 3
-  resources:
-    limits:
-      cpu: 1000m
-      memory: 1Gi
-    requests:
-      cpu: 500m
-      memory: 512Mi
-  autoscaling:
-    enabled: true
-    minReplicas: 3
-    maxReplicas: 10
-    targetCPUUtilizationPercentage: 75
-
-# Ingress configuration
-ingress:
-  enabled: true
-  className: nginx
-  annotations:
-    cert-manager.io/cluster-issuer: letsencrypt-prod
-    nginx.ingress.kubernetes.io/rate-limit: "100"
-    nginx.ingress.kubernetes.io/rate-limit-window: "1m"
-  hosts:
-    - host: api.aitbc.io
-      paths:
-        - path: /
-          pathType: Prefix
-  tls:
-    - secretName: prod-tls
-      hosts:
-        - api.aitbc.io
-
-# Security
-podSecurityPolicy:
-  enabled: true
-
-networkPolicy:
-  enabled: true
-
-# Backup configuration
-backup:
-  enabled: true
-  schedule: "0 2 * * *"
-  retention: "30d"