[management,proxy] Agent network: per-account LLM gateway (policy, metering, multi-provider) (#6555)

* [agent-network] Shared proto, OpenAPI schema, and generated types

* [agent-network] Management: store, manager, synthesizer, policy engine, provider catalog, HTTP/gRPC API

Adds the account-scoped agent-network module: provider/policy/budget CRUD and
store, the reverse-proxy service synthesizer, policy selection + limit
enforcement, the provider catalog (incl. Vertex AI and AWS Bedrock entries),
and the management HTTP + proxy gRPC surfaces.

* [management] Fix agent-network proxy-peer fan-out on affected-peer recompute

The affected-peers resolver loaded only persisted reverse-proxy services, but
agent-network services are synthesized on demand and never persisted. As a
result the embedded proxy peer was never folded into the affected set when a
client's group changed, so the proxy received no network-map update for a newly
authorised client and rejected its handshake until a full resync (restart).

loadProxyServices now merges the synthesized agent-network services (injected
via a registration hook to avoid an import cycle), so proxy peers learn newly
authorised clients immediately.

* [proxy] Reverse-proxy middleware framework, chain, and request plumbing

The per-target middleware chain (slots, dispatcher, mutation gate, metadata
merger), body capture, access-log terminal sink, and the proxy wiring that
builds + runs chains for synthesized agent-network services.

* [proxy] LLM parsers, pricing, and builtin middlewares (OpenAI, Anthropic, Vertex AI, AWS Bedrock)

Request/response parsers and SSE/event-stream metering, the embedded pricing
table, and the builtin middleware set: request parser, router, policy
limit-check/record, cost meter, guardrail, identity inject, response parser.
Includes the path-routed providers — Google Vertex AI (keyfile:: service-account
OAuth minting) and AWS Bedrock (bearer auth, invoke/converse/streaming, optional
/bedrock prefix) — plus the Models allowlist and unmeterable-publisher deny.

* [proxy] IPv6 in-place apply and TCP accept-loop hardening on netstack listeners

* [agent-network] End-to-end test suite, module docs, and deployment preset

* [agent-network] Fix codespell typos and exclude false positives

- labelgen word pool: vermillion -> vermilion, racoon -> raccoon.
- codespell ignore list: add flate (Go compress/flate package), recordin
  (a test-local identifier), and unparseable (a valid alternative spelling used
  consistently across identifiers + a metadata-value constant).

* [management] Set LastSeen on injected proxy peer in realstack test (MySQL strict-mode)

The injected embedded proxy peer had a PeerStatus with a zero LastSeen, which
serializes to '0000-00-00' and is rejected by MySQL in strict mode (SQLite
tolerates it). Set LastSeen to a valid time so SaveAccount succeeds on both
engines.

* [agent-network] Remove e2e shell-script suite from this branch

The end-to-end shell scripts under scripts/e2e/ are maintained in a separate
testing suite and are not part of this change set.

* [agent-network] Polish module docs: remove internal review scaffolding, fix links, verify diagrams

Strip PR-review framing, commit references, absolute paths, and stale internal
references from the agent-network module docs; fix broken relative links; verify
all diagrams against the current architecture. Remove the internal AI-reviewer
prompt file.

* [management] Refine session expiration handling to support 3-state encoding for SSO deadlines

* [agent-network] Relocate agentnetwork package to internals/modules

Move management/server/agentnetwork (and its catalog/, labelgen/, types/
subpackages) to management/internals/modules/agentnetwork, alongside the
reverse-proxy module, and rewrite all importers. Pure relocation: package names,
the synthesizer + affectedpeers registration hook, and store access (shared
store.Store) are unchanged, so no import cycle is introduced (affectedpeers
still depends only on the agentnetwork/types leaf).

* [agent-network] Co-locate HTTP handlers in the module (RegisterEndpoints)

Move the agent-network HTTP handlers from server/http/handlers/agentnetwork into
the module at internals/modules/agentnetwork/handlers (package handlers) and
rename the entrypoint AddEndpoints -> RegisterEndpoints, matching the
reverse-proxy module convention. Wiring in http/handler.go updated accordingly.

infrastructure_files/getting-started.sh

@@ -398,7 +398,42 @@ configure_domain() {
   return 0
 }
 
+apply_agent_network_preset() {
+  # Agent-network turnkey install: built-in Traefik + NetBird Proxy with
+  # NB_PROXY_PRIVATE=true, dashboard locked to agent-network-only mode.
+  # Bypasses every reverse-proxy / proxy / CrowdSec prompt. The only
+  # inputs we still need from the operator are the domain (handled by
+  # configure_domain via NETBIRD_DOMAIN env var or interactive prompt)
+  # and the ACME email — both honor env vars first and fall back to a
+  # prompt only when unset. CrowdSec is intentionally off.
+  REVERSE_PROXY_TYPE="0"
+  ENABLE_PROXY="true"
+  ENABLE_CROWDSEC="false"
+
+  if [[ -n "${NETBIRD_LETSENCRYPT_EMAIL}" ]]; then
+    TRAEFIK_ACME_EMAIL="${NETBIRD_LETSENCRYPT_EMAIL}"
+  else
+    TRAEFIK_ACME_EMAIL=$(read_traefik_acme_email)
+  fi
+
+  echo "" > /dev/stderr
+  echo "Agent-network preset enabled (NETBIRD_AGENT_NETWORK=true):" > /dev/stderr
+  echo "  - reverse proxy: built-in Traefik" > /dev/stderr
+  echo "  - NetBird Proxy: enabled with NB_PROXY_PRIVATE=true" > /dev/stderr
+  echo "  - dashboard: NETBIRD_AGENT_NETWORK_ONLY=true" > /dev/stderr
+  echo "  - CrowdSec: disabled" > /dev/stderr
+  echo "  - Let's Encrypt email: ${TRAEFIK_ACME_EMAIL}" > /dev/stderr
+  echo "" > /dev/stderr
+}
+
 configure_reverse_proxy() {
+  # Short-circuit: agent-network preset locks every reverse-proxy /
+  # proxy / CrowdSec choice and bypasses the interactive prompts.
+  if [[ "${NETBIRD_AGENT_NETWORK}" == "true" ]]; then
+    apply_agent_network_preset
+    return 0
+  fi
+
   # Prompt for reverse proxy type
   REVERSE_PROXY_TYPE=$(read_reverse_proxy_type)
 
@@ -910,6 +945,15 @@ NGINX_SSL_PORT=443
 # Letsencrypt
 LETSENCRYPT_DOMAIN=none
 EOF
+
+  if [[ "${NETBIRD_AGENT_NETWORK}" == "true" ]]; then
+    cat <<EOF
+# Agent-network preset: dashboard hides the standard NetBird surfaces
+# and exposes only the AI Observability + agent-network configuration
+# pages. Paired with NB_PROXY_PRIVATE=true on the proxy side.
+NETBIRD_AGENT_NETWORK_ONLY=true
+EOF
+  fi
   return 0
 }
 
@@ -946,6 +990,17 @@ NB_PROXY_PROXY_PROTOCOL=true
 NB_PROXY_TRUSTED_PROXIES=$TRAEFIK_IP
 EOF
 
+  if [[ "${NETBIRD_AGENT_NETWORK}" == "true" ]]; then
+    cat <<EOF
+# Agent-network preset: turn the proxy into the private reverse-proxy
+# ingress for agent-network synth services. Disables the public-facing
+# surface so the proxy serves only synth-generated routes (the
+# llm_router-driven LLM endpoints) and the per-account inbound
+# listeners on the embedded netstack.
+NB_PROXY_PRIVATE=true
+EOF
+  fi
+
   if [[ "$ENABLE_CROWDSEC" == "true" && -n "$CROWDSEC_BOUNCER_KEY" ]]; then
     cat <<EOF
 NB_PROXY_CROWDSEC_API_URL=http://crowdsec:8080