feat: zoneless Angular + EntityCache stale-while-revalidate + ESLint boundaries + service layering

Zoneless:
- Remove zone.js from build polyfills, add provideZonelessChangeDetection()
- Delete src/polyfills.ts

EntityCache:
- Add optional TTL and stale-while-revalidate to EntityCache
- background re-fetch with inflight dedup Map
- ProgramRepository (5 min), CoursesRepository.detailCache (10 min)
- Remove manual invalidate() from VacancyRepository and ProjectRepository

ESLint:
- Upgrade ESLint 8→9, @typescript-eslint 5→8, Prettier 2→3
- New eslint.config.mjs with eslint-plugin-boundaries v6 flat config
- Boundaries: default disallow, all cross-layer deps explicitly allowed

Service layering:
- Move NavService, SnackbarService, SnackModel, LoadingService to api/shared/
- Move StorageService to domain/shared/, ChatStateService to domain/shared/
- Update all imports across codebase, delete old files

Author: Awakich

.eslintrc.json

@@ -1,10 +1,8 @@
-# @format
-
 {
   "singleQuote": false,
   "semi": true,
   "printWidth": 100,
   "insertPragma": true,
   "arrowParens": "avoid",
-  "bracketSameLine": false,
+  "bracketSameLine": false
 }

.prettierrc

@@ -24,7 +24,6 @@
               "base": "dist/social_platform"
             },
             "index": "projects/social_platform/src/index.html",
-            "polyfills": ["zone.js"],
             "tsConfig": "projects/social_platform/tsconfig.app.json",
             "inlineStyleLanguage": "scss",
             "assets": [

angular.json

@@ -0,0 +1,138 @@
+import js from "@eslint/js";
+import ts from "typescript-eslint";
+import prettier from "eslint-config-prettier";
+import boundaries from "eslint-plugin-boundaries";
+import globals from "globals";
+
+export default ts.config(
+  {
+    ignores: [
+      "**/node_modules/**",
+      "**/dist/**",
+      "**/coverage/**",
+      "**/.angular/**",
+      "**/*.scss",
+    ],
+  },
+  js.configs.recommended,
+  ...ts.configs.recommended,
+  prettier,
+  {
+    languageOptions: {
+      ecmaVersion: "latest",
+      sourceType: "module",
+      globals: {
+        ...globals.browser,
+        ...globals.jasmine,
+      },
+    },
+    plugins: {
+      boundaries,
+    },
+    settings: {
+      "boundaries/dependency-nodes": ["import"],
+      "boundaries/include": ["projects/**/*.ts"],
+      "boundaries/elements": [
+        {
+          type: "domain",
+          pattern: "projects/social_platform/src/app/domain/**",
+          mode: "full",
+        },
+        {
+          type: "infrastructure",
+          pattern: "projects/social_platform/src/app/infrastructure/**",
+          mode: "full",
+        },
+        {
+          type: "api",
+          pattern: "projects/social_platform/src/app/api/**",
+          mode: "full",
+        },
+        {
+          type: "ui",
+          pattern: "projects/social_platform/src/app/ui/**",
+          mode: "full",
+        },
+        {
+          type: "utils",
+          pattern: "projects/social_platform/src/app/utils/**",
+          mode: "full",
+        },
+        {
+          type: "testing",
+          pattern: "projects/social_platform/src/app/testing/**",
+          mode: "full",
+        },
+        {
+          type: "core-lib",
+          pattern: "projects/core/src/**",
+          mode: "full",
+        },
+        {
+          type: "ui-lib",
+          pattern: "projects/ui/src/**",
+          mode: "full",
+        },
+        {
+          type: "env",
+          pattern: "projects/social_platform/src/environments/**",
+          mode: "full",
+        },
+        {
+          type: "root",
+          pattern: [
+            "projects/social_platform/src/app/app.component.ts",
+            "projects/social_platform/src/app/app.component.spec.ts",
+            "projects/social_platform/src/app/app.config.ts",
+            "projects/social_platform/src/app/app.routes.ts",
+            "projects/social_platform/src/app/sentry.config.ts",
+            "projects/social_platform/src/main.ts",
+            "projects/social_platform/src/test.ts",
+          ],
+          mode: "full",
+        },
+      ],
+      "import/resolver": {
+        typescript: {
+          alwaysTryTypes: true,
+          project: ["./tsconfig.json"],
+        },
+      },
+    },
+    rules: {
+      "no-useless-constructor": "off",
+      "@typescript-eslint/no-empty-function": "off",
+      "no-empty": "off",
+      "dot-notation": "off",
+      "lines-between-class-members": "off",
+      "@typescript-eslint/no-explicit-any": "off",
+      "@typescript-eslint/no-unused-vars": "off",
+      "@typescript-eslint/no-unused-expressions": "off",
+
+      "boundaries/no-unknown": ["error"],
+      "boundaries/no-unknown-files": ["error"],
+      "boundaries/dependencies": [
+        "error",
+        {
+          default: "disallow",
+          rules: [
+            { from: { type: "domain" }, allow: { to: { type: ["domain", "core-lib"] } } },
+            { from: { type: "infrastructure" }, allow: { to: { type: ["domain", "infrastructure", "core-lib", "utils"] } } },
+            { from: { type: "api" }, allow: { to: { type: ["domain", "infrastructure", "api", "core-lib", "utils", "env"] } } },
+            { from: { type: "ui" }, allow: { to: { type: ["domain", "infrastructure", "api", "ui", "core-lib", "ui-lib", "utils"] } } },
+            { from: { type: "utils" }, allow: { to: { type: ["domain", "core-lib", "utils"] } } },
+            { from: { type: "core-lib" }, allow: { to: { type: ["core-lib", "domain", "utils", "env"] } } },
+            { from: { type: "ui-lib" }, allow: { to: { type: ["core-lib", "domain", "ui-lib"] } } },
+            { from: { type: "root" }, allow: { to: { type: ["domain", "infrastructure", "api", "ui", "core-lib", "ui-lib", "utils", "env", "root"] } } },
+          ],
+        },
+      ],
+    },
+  },
+  {
+    files: ["**/*.spec.ts"],
+    rules: {
+      "boundaries/dependencies": "off",
+    },
+  }
+);