[traefik] Remove broken rewrite-body plugin and all rybbit/anti-AI injection

The rewrite-body Traefik plugin (both packruler/rewrite-body v1.2.0 and
the-ccsn/traefik-plugin-rewritebody v0.1.3) silently fails on Traefik
v3.6.12 due to Yaegi interpreter issues with ResponseWriter wrapping.
Both plugins load without errors but never inject content.

Removed:
- rewrite-body plugin download (init container) and registration
- strip-accept-encoding middleware (only existed for rewrite-body bug)
- anti-ai-trap-links middleware (used rewrite-body for injection)
- rybbit_site_id variable from ingress_factory and reverse_proxy factory
- rybbit_site_id from 25 service stacks (39 instances)
- Per-service rybbit-analytics middleware CRD resources

Kept:
- compress middleware (entrypoint-level, working correctly)
- ai-bot-block middleware (ForwardAuth to bot-block-proxy)
- anti-ai-headers middleware (X-Robots-Tag: noai, noimageai)
- All CrowdSec, Authentik, rate-limit middleware unchanged

Next: Cloudflare Workers with HTMLRewriter for edge-side injection.

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

stacks/mailserver/modules/mailserver/roundcubemail.tf

@@ -263,7 +263,6 @@ module "ingress" {
   name            = "mail"
   service_name    = "roundcubemail"
   tls_secret_name = var.tls_secret_name
-  rybbit_site_id  = "082f164faa7d"
   extra_annotations = {
     "gethomepage.dev/enabled"      = "true"
     "gethomepage.dev/name"         = "Roundcube Mail"