[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/k8s-portal/files/package.json

@@ -0,0 +1,24 @@
+{
+	"name": "files",
+	"private": true,
+	"version": "0.0.1",
+	"type": "module",
+	"scripts": {
+		"dev": "vite dev",
+		"build": "vite build",
+		"preview": "vite preview",
+		"prepare": "svelte-kit sync || echo ''",
+		"check": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json",
+		"check:watch": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json --watch"
+	},
+	"devDependencies": {
+		"@sveltejs/adapter-auto": "^7.0.0",
+		"@sveltejs/adapter-node": "^5.5.3",
+		"@sveltejs/kit": "^2.50.2",
+		"@sveltejs/vite-plugin-svelte": "^6.2.4",
+		"svelte": "^5.49.2",
+		"svelte-check": "^4.3.6",
+		"typescript": "^5.9.3",
+		"vite": "^7.3.1"
+	}
+}