[ci skip] Move Terraform modules into stack directories

Move all 88 service modules (66 individual + 22 platform) from
modules/kubernetes/<service>/ into their corresponding stack directories:

- Service stacks: stacks/<service>/module/
- Platform stack: stacks/platform/modules/<service>/

This collocates module source code with its Terragrunt definition.
Only shared utility modules remain in modules/kubernetes/:
ingress_factory, setup_tls_secret, dockerhub_secret, oauth-proxy.

All cross-references to shared modules updated to use correct
relative paths. Verified with terragrunt run --all -- plan:
0 adds, 0 destroys across all 68 stacks.

stacks/platform/modules/cloudflared/main.tf

@@ -0,0 +1,90 @@
+# Contents for cloudflare tunnel
+
+variable "tls_secret_name" {}
+variable "cloudflare_tunnel_token" {}
+resource "kubernetes_namespace" "cloudflared" {
+  metadata {
+    name = "cloudflared"
+    labels = {
+      tier = var.tier
+    }
+  }
+}
+variable "tier" { type = string }
+
+module "tls_secret" {
+  source          = "../../../../modules/kubernetes/setup_tls_secret"
+  namespace       = kubernetes_namespace.cloudflared.metadata[0].name
+  tls_secret_name = var.tls_secret_name
+}
+
+resource "kubernetes_deployment" "cloudflared" {
+  metadata {
+    name      = "cloudflared"
+    namespace = kubernetes_namespace.cloudflared.metadata[0].name
+    labels = {
+      app  = "cloudflared"
+      tier = var.tier
+    }
+    annotations = {
+      "reloader.stakater.com/search" = "true"
+    }
+  }
+  spec {
+    replicas = 3
+    strategy {
+      type = "RollingUpdate"
+    }
+    selector {
+      match_labels = {
+        app = "cloudflared"
+      }
+    }
+    template {
+      metadata {
+        labels = {
+          app = "cloudflared"
+        }
+      }
+      spec {
+        container {
+          # image = "wisdomsky/cloudflared-web:latest"
+          image   = "cloudflare/cloudflared"
+          name    = "cloudflared"
+          command = ["cloudflared", "tunnel", "run"]
+          env {
+            name  = "TUNNEL_TOKEN"
+            value = var.cloudflare_tunnel_token
+          }
+
+          port {
+            container_port = 14333
+          }
+        }
+      }
+    }
+  }
+}
+
+resource "kubernetes_service" "cloudflared" {
+  metadata {
+    name      = "cloudflared"
+    namespace = kubernetes_namespace.cloudflared.metadata[0].name
+    labels = {
+      "app" = "cloudflared"
+    }
+  }
+
+  spec {
+    selector = {
+      app = "cloudflared"
+    }
+    port {
+      name        = "http"
+      target_port = 14333
+      port        = 80
+      protocol    = "TCP"
+    }
+  }
+}
+