feat(orchestrator): carry envd-version on build-path sandbox LD context

Drive the envd-version attribute off Config.Envd.Version in the shared
sandboxLDContext helper so it is present on both regular and build
sandboxes (envd version is resolved during build). Switch the
freeze-user-cgroup and reclaim-config evals to this helper so they no
longer depend on server-side ctx propagation, which the build path does
not run.

Author: jakubno

packages/orchestrator/pkg/sandbox/reclaim.go

@@ -62,14 +62,16 @@ func (s *Sandbox) bestEffortReclaim(ctx context.Context) {
 	ctx, span := tracer.Start(ctx, "envd-reclaim")
 	defer span.End()
 
+	sbxCtx := sandboxLDContext(s.Runtime, s.Config)
+
 	cfg := featureflags.GetReclaimConfig(ctx, s.featureFlags,
-		featureflags.SandboxContext(s.Runtime.SandboxID),
+		sbxCtx,
 		featureflags.TeamContext(s.Runtime.TeamID),
 		featureflags.TemplateContext(s.Runtime.TemplateID),
 	)
 
 	if s.featureFlags.BoolFlag(ctx, featureflags.FreezeUserCgroupFlag,
-		featureflags.SandboxContext(s.Runtime.SandboxID),
+		sbxCtx,
 		featureflags.TeamContext(s.Runtime.TeamID),
 		featureflags.TemplateContext(s.Runtime.TemplateID),
 	) {

packages/orchestrator/pkg/sandbox/sandbox.go

@@ -183,7 +183,7 @@ type RuntimeMetadata struct {
 	SandboxType SandboxType
 }
 
-// sandboxLDContext builds an LD context with kernel/FC-version attributes for
+// sandboxLDContext builds an LD context with envd/kernel/FC-version attributes for
 // per-sandbox flag targeting. Team/template targeting comes from the team and
 // template contexts the caller embeds in ctx.
 func sandboxLDContext(runtime RuntimeMetadata, config *Config) ldcontext.Context {
@@ -192,6 +192,7 @@ func sandboxLDContext(runtime RuntimeMetadata, config *Config) ldcontext.Context
 		SetString(featureflags.SandboxTemplateAttribute, runtime.TemplateID).
 		SetString(featureflags.SandboxKernelVersionAttribute, config.FirecrackerConfig.KernelVersion).
 		SetString(featureflags.SandboxFirecrackerVersionAttribute, config.FirecrackerConfig.FirecrackerVersion).
+		SetString(featureflags.SandboxEnvdVersionAttribute, config.Envd.Version).
 		SetString(featureflags.SandboxTypeAttribute, runtime.SandboxType.String()).
 		Build()
 }