Docs: update proxy architecture for upstream keepalive

Update flyio-proxy, forgejo, routing, manage-flyio-proxy,
expose-service-publicly, and mise-tasks docs to reflect:

- Upstream keepalive pools replacing variable-based proxy_pass
- proxy_ssl_name requirement for upstream blocks
- MagicDNS readiness check in start.sh
- fly-reload task for DNS re-resolution
- Crawler mitigation (robots.txt, archive redirect, release caching)
- Forgejo /metrics endpoint and archive cleanup cron
- cv.eblu.me in routing and exposed services tables
- upstream_response_time histogram metric
- Changelog fragment

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/reference/infrastructure/routing.md

@@ -1,6 +1,6 @@
 ---
 title: Routing
-modified: 2026-03-03
+modified: 2026-04-17
 tags:
   - infrastructure
   - networking
@@ -51,6 +51,7 @@ DNS CNAMEs point to `blumeops-proxy.fly.dev`. TLS via Fly.io-managed Let's Encry
 | Service | URL | Description |
 |---------|-----|-------------|
 | [[docs]] | https://docs.eblu.me | Documentation site |
+| [[cv]] | https://cv.eblu.me | CV / resume |
 | [[forgejo]] | https://forge.eblu.me | Git hosting (public) |
 
 ## Tailscale-Only Services