Add system memory monitoring, Bedrock support, and Discord integrations

- Add CPU/GPU memory monitoring endpoint and frontend widget
- Add Amazon Bedrock model support (API key / inference profiles) plus model selector entries
- Add Discord weather/laundry notification job (JMA forecast + LLM-generated message)
- Add Discord bot that replies to mentions via the configured LLM, with weather-aware context
- Add scheduled "useless tips" job with separate webhook and quiet-hours skip
- Switch FastAPI startup to lifespan handler, log viewer, markdown rendering, and toast UI additions

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/stores/chat.ts

@@ -1,31 +1,61 @@
 import { defineStore } from 'pinia'
 import { ref, computed } from 'vue'
-import { fetchSessions, deleteSession, streamChat, type SessionInfo } from '../api/client'
+import { fetchSessions, fetchMessages, deleteSession, streamChat, type SessionInfo } from '../api/client'
 
 export interface Message {
   role: 'user' | 'assistant'
   content: string
   pending?: boolean
+  error?: boolean
 }
 
+export interface Toast {
+  id: number
+  message: string
+}
+
+let toastSeq = 0
+
 export const useChatStore = defineStore('chat', () => {
   const sessions = ref<SessionInfo[]>([])
   const currentSessionId = ref<string | null>(null)
   const messages = ref<Message[]>([])
   const isStreaming = ref(false)
-  const selectedModel = ref('gpt-4o')
+  const selectedModel = ref('gpt-5.4')
+  const toasts = ref<Toast[]>([])
 
   const currentSession = computed(() =>
     sessions.value.find((s) => s.id === currentSessionId.value) ?? null,
   )
 
+  function pushToast(message: string, durationMs = 5000) {
+    const id = ++toastSeq
+    toasts.value.push({ id, message })
+    setTimeout(() => {
+      toasts.value = toasts.value.filter((t) => t.id !== id)
+    }, durationMs)
+  }
+
+  function dismissToast(id: number) {
+    toasts.value = toasts.value.filter((t) => t.id !== id)
+  }
+
   async function loadSessions() {
     sessions.value = await fetchSessions()
   }
 
-  function selectSession(sessionId: string | null) {
+  async function selectSession(sessionId: string | null) {
     currentSessionId.value = sessionId
     messages.value = []
+    if (!sessionId) return
+    try {
+      const records = await fetchMessages(sessionId)
+      messages.value = records
+        .filter((r) => r.role === 'user' || r.role === 'assistant')
+        .map((r) => ({ role: r.role as 'user' | 'assistant', content: r.content }))
+    } catch (e) {
+      pushToast(`メッセージ取得失敗: ${e instanceof Error ? e.message : e}`)
+    }
   }
 
   async function removeSession(sessionId: string) {
@@ -41,8 +71,8 @@ export const useChatStore = defineStore('chat', () => {
     if (isStreaming.value || !text.trim()) return
 
     messages.value.push({ role: 'user', content: text })
-    const assistantMsg: Message = { role: 'assistant', content: '', pending: true }
-    messages.value.push(assistantMsg)
+    messages.value.push({ role: 'assistant', content: '', pending: true })
+    const msgIdx = messages.value.length - 1  // reactive proxy 経由で更新するためインデックスを保持
     isStreaming.value = true
 
     streamChat(
@@ -52,18 +82,24 @@ export const useChatStore = defineStore('chat', () => {
       (chunk) => {
         if (chunk.type === 'session_id' && chunk.value) {
           currentSessionId.value = chunk.value
-          loadSessions()
+          loadSessions().catch((e) => pushToast(`セッション更新失敗: ${e.message}`))
         } else if (chunk.type === 'chunk' && chunk.value) {
-          assistantMsg.content += chunk.value
+          messages.value[msgIdx].content += chunk.value
         } else if (chunk.type === 'done') {
-          assistantMsg.pending = false
+          messages.value[msgIdx].pending = false
+          isStreaming.value = false
+          loadSessions().catch((e) => pushToast(`セッション更新失敗: ${e.message}`))
+        } else if (chunk.type === 'error') {
+          messages.value[msgIdx].content = chunk.value ?? 'バックエンドでエラーが発生しました。'
+          messages.value[msgIdx].pending = false
+          messages.value[msgIdx].error = true
           isStreaming.value = false
-          loadSessions()
         }
       },
-      (_err) => {
-        assistantMsg.content = 'エラーが発生しました。'
-        assistantMsg.pending = false
+      (err) => {
+        messages.value[msgIdx].content = err.message
+        messages.value[msgIdx].pending = false
+        messages.value[msgIdx].error = true
         isStreaming.value = false
       },
     )
@@ -75,7 +111,10 @@ export const useChatStore = defineStore('chat', () => {
     messages,
     isStreaming,
     selectedModel,
+    toasts,
     currentSession,
+    pushToast,
+    dismissToast,
     loadSessions,
     selectSession,
     removeSession,