fix(app): Web 平台兼容性修复 + 字体资源 + API base URL

- 添加 Web/Windows 平台支持 (flutter create --platforms)
- 下载字体资源 (NotoSansSC/Caveat Regular+Bold)
- Isar 3.x Web 不兼容：添加 kIsWeb 守卫，Web 上跳过 Isar 初始化
- IsarJournalRepository: instance 返回 nullable，Web 上使用 RemoteJournalRepository
- SyncEngine: persistPendingQueue/restorePendingQueue Web 安全
- SettingsBloc: 从 RepositoryProvider 改为 ListenableProvider
- ApiClient base URL: 8080 → 3000 匹配后端端口
- Isar .g.dart: 64 位 ID 替换为 JS 安全范围值

app/lib/data/local/collections/journal_element_collection.g.dart

@@ -16,7 +16,7 @@ extension GetJournalElementCollectionCollection on Isar {
 
 const JournalElementCollectionSchema = CollectionSchema(
   name: r'JournalElementCollection',
-  id: -3625932583395690305,
+  id: 5678901234567001,
   properties: {
     r'contentJson': PropertySchema(
       id: 0,
@@ -96,7 +96,7 @@ const JournalElementCollectionSchema = CollectionSchema(
   idName: r'isarId',
   indexes: {
     r'id': IndexSchema(
-      id: -3268401673993471357,
+      id: 5678901234567002,
       name: r'id',
       unique: false,
       replace: false,
@@ -109,7 +109,7 @@ const JournalElementCollectionSchema = CollectionSchema(
       ],
     ),
     r'journalId': IndexSchema(
-      id: 1745640946427815323,
+      id: 5678901234567003,
       name: r'journalId',
       unique: false,
       replace: false,

app/lib/data/local/collections/journal_entry_collection.g.dart

@@ -16,7 +16,7 @@ extension GetJournalEntryCollectionCollection on Isar {
 
 const JournalEntryCollectionSchema = CollectionSchema(
   name: r'JournalEntryCollection',
-  id: -6325316395299921961,
+  id: 5678901234567004,
   properties: {
     r'assignedTopicId': PropertySchema(
       id: 0,
@@ -101,7 +101,7 @@ const JournalEntryCollectionSchema = CollectionSchema(
   idName: r'isarId',
   indexes: {
     r'id': IndexSchema(
-      id: -3268401673993471357,
+      id: 5678901234567002,
       name: r'id',
       unique: false,
       replace: false,

app/lib/data/local/collections/pending_operation_collection.g.dart

@@ -16,7 +16,7 @@ extension GetPendingOperationCollectionCollection on Isar {
 
 const PendingOperationCollectionSchema = CollectionSchema(
   name: r'PendingOperationCollection',
-  id: -6885010264946527864,
+  id: 5678901234567005,
   properties: {
     r'createdAtEpoch': PropertySchema(
       id: 0,
@@ -61,7 +61,7 @@ const PendingOperationCollectionSchema = CollectionSchema(
   idName: r'isarId',
   indexes: {
     r'id': IndexSchema(
-      id: -3268401673993471357,
+      id: 5678901234567002,
       name: r'id',
       unique: false,
       replace: false,