Add OrgAvatar component and frontend-utils package

- Create @reviq/frontend-utils package for frontend-specific utilities
- Add OrgAvatar component with size variants (xs, sm, md, lg, xl)
- Display org initials with deterministic colors when no logo available
- Add getOrgInitials and getOrgColor utility functions
- Update org-switcher and all org display pages to use OrgAvatar
- Add noNonNullAssertion lint rule as error in biome.jsonc

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

bun.lock

@@ -78,6 +78,7 @@
         "@orpc/contract": "^1.13.2",
         "@reviq/api-contract": "workspace:*",
         "@reviq/common": "workspace:*",
+        "@reviq/frontend-utils": "workspace:*",
         "@simplewebauthn/browser": "^13.2.2",
         "@tanstack/svelte-query": "^6.0.14",
         "@tanstack/svelte-query-devtools": "^6.0.3",
@@ -180,6 +181,17 @@
         "typescript": "catalog:",
       },
     },
+    "packages/frontend-utils": {
+      "name": "@reviq/frontend-utils",
+      "version": "0.0.1",
+      "devDependencies": {
+        "@macalinao/eslint-config": "catalog:",
+        "@macalinao/tsconfig": "catalog:",
+        "@types/bun": "catalog:",
+        "eslint": "catalog:",
+        "typescript": "catalog:",
+      },
+    },
     "packages/testing/virtual-authenticator": {
       "name": "@reviq/virtual-authenticator",
       "version": "0.0.1",
@@ -425,6 +437,8 @@
 
     "@reviq/db-schema": ["@reviq/db-schema@workspace:packages/db-schema"],
 
+    "@reviq/frontend-utils": ["@reviq/frontend-utils@workspace:packages/frontend-utils"],
+
     "@reviq/utils": ["@reviq/utils@workspace:packages/utils"],
 
     "@reviq/virtual-authenticator": ["@reviq/virtual-authenticator@workspace:packages/testing/virtual-authenticator"],