chore(nx): commit Nx workspace config, drop angular.json

The repo was mid-migration between angular.json and an Nx-style
project.json + nx.json setup. project.json was already committed but
nx.json sat untracked locally and angular.json was deleted-but-not-staged.
CI checks out only the committed state, so without nx.json Nx had no
workspace config and the production build target failed.

Add nx.json to the index, drop angular.json. Cloud cache is removed from
nx.json so CI does not require an Nx Cloud token.

bun.lock changes from the migration remain uncommitted for now.

Author: Confitty Developer

angular.json

@@ -0,0 +1,15 @@
+{
+  "$schema": "./node_modules/nx/schemas/nx-schema.json",
+  "targetDefaults": {
+    "build": {
+      "cache": true,
+      "dependsOn": ["^build"],
+      "inputs": ["production", "^production"]
+    }
+  },
+  "namedInputs": {
+    "sharedGlobals": [],
+    "default": ["{projectRoot}/**/*", "sharedGlobals"],
+    "production": ["default"]
+  }
+}