feat(core)!: introduce runtime extension registry and flat module conventions

BREAKING CHANGE: sup config now derives entries from package.json#exports and a server/client glob instead of manual lists; module structure follows flat + barrel convention with .server.js/.client.js runtime suffixes

src/shared/components/Loading.js

@@ -1,7 +1,7 @@
 'use client';
 
 import React from 'react';
-import { Recycle03Icon } from '../Icons';
+import { Recycle03Icon } from '../icons/index.js';
 
 const Loading = ({ size = 'md' }) => {
     const sizes = {

src/shared/components/Modal.js

@@ -1,6 +1,6 @@
 import React from 'react';
 import { Dialog } from '@headlessui/react';
-import { Cancel01Icon } from '../Icons';
+import { Cancel01Icon } from '../icons/index.js';
 import Button from './Button';
 
 const Modal = ({

src/shared/components/Table.js

@@ -2,7 +2,7 @@
 
 import React from 'react';
 import Badge from './Badge';
-import { TorriGateIcon } from '../Icons';
+import { TorriGateIcon } from '../icons/index.js';
 
 const ROW_SIZE = {
     sm: { cell: 'px-4 py-[11px]', header: 'px-4 py-[9px]', mobile: 'p-4' },

src/shared/lib/init.js

@@ -16,7 +16,7 @@
 
 import { configureRouter, registerFeatureRoutes, clearRouterConfig, clearFeatureRoutes } from '@zen/core/api';
 import { registerStoragePolicies, clearStorageConfig } from '@zen/core/storage';
-import { validateSession } from '../../features/auth/lib/session.js';
+import { validateSession } from '../../features/auth/session.js';
 import { routes as authRoutes } from '../../features/auth/api.js';
 import { storageAccessPolicies } from '../../features/auth/storage-policies.js';
 import { done, warn } from './logger.js';