feat(netbird): manifest-driven migration via reusable orchestrator primitives

Migrate the netbird stack (server/dashboard/proxy) off ~500 lines of per-app Rust
to 3 declarative manifests, adding 4 reusable primitives:
- SecretGenKind::Base64 (netbird relay authSecret + sqlite store encryptionKey)
- GeneratedCert schema + ensure_manifest_certs (self-signed TLS so the dashboard
  gets a secure context for OIDC PKCE — issue #15; https proxy on 8087 preserved)
- templated GeneratedFile render: {{HOST_IP}}/{{HOST_MDNS}}/{{NETWORK_GATEWAY}}
  (aardvark resolver for the #15 stale-IP fix) /{{secret:NAME}} (never logged)
- legacy create_container now honours port.protocol (3478/udp STUN)
install_netbird_stack routes via the orchestrator first (legacy kept as fallback,
mirroring indeedhub); launch URL derives https://{host_ip}:8087 from host facts.
Legacy Rust deletion deferred to post-live-verify.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

core/container/src/lib.rs

@@ -8,8 +8,9 @@ pub mod runtime;
 pub use bitcoin_simulator::{BitcoinSimulationMode, BitcoinSimulator};
 pub use health_monitor::HealthMonitor;
 pub use manifest::{
-    AppInterface, AppManifest, BuildConfig, ContainerConfig, Dependency, DerivedEnv, GeneratedFile,
-    GeneratedSecret, HealthCheck, HookStep, HostCopy, HostFacts, LifecycleHooks, ManifestError,
+    AppInterface, AppManifest, BuildConfig, ContainerConfig, Dependency, DerivedEnv, GeneratedCert,
+    GeneratedFile, GeneratedSecret, HealthCheck, HookStep, HostCopy, HostFacts, LifecycleHooks,
+    ManifestError,
     ResolvedSource, ResourceLimits, SecretEnv, SecretGenKind, SecretsProvider, SecurityPolicy,
     Volume,
 };