refactor(hooks): fix empty catches and remove AI slop from code comments

src/hooks/model-fallback/chat-message-fallback-handler.ts

@@ -0,0 +1,74 @@
+import { log } from "../../shared/logger"
+import { getTaskToastManager } from "../../features/task-toast-manager"
+import type { ChatMessageHandlerOutput, ChatMessageInput } from "../../plugin/chat-message"
+
+export async function applyFallbackToChatMessage(params: {
+  input: ChatMessageInput
+  output: ChatMessageHandlerOutput
+  fallback: { providerID: string; modelID: string; variant?: string }
+  toast?: (input: {
+    title: string
+    message: string
+    variant?: "info" | "success" | "warning" | "error"
+    duration?: number
+  }) => void | Promise<void>
+  onApplied?: (input: {
+    sessionID: string
+    providerID: string
+    modelID: string
+    variant?: string
+  }) => void | Promise<void>
+  lastToastKey: Map<string, string>
+}): Promise<void> {
+  const { input, output, fallback, toast, onApplied, lastToastKey } = params
+  const { sessionID } = input
+  if (!sessionID) return
+
+  output.message["model"] = {
+    providerID: fallback.providerID,
+    modelID: fallback.modelID,
+  }
+  if (fallback.variant !== undefined) {
+    output.message["variant"] = fallback.variant
+  } else {
+    delete output.message["variant"]
+  }
+
+  if (toast) {
+    const key = `${sessionID}:${fallback.providerID}/${fallback.modelID}:${fallback.variant ?? ""}`
+    if (lastToastKey.get(sessionID) !== key) {
+      lastToastKey.set(sessionID, key)
+      const variantLabel = fallback.variant ? ` (${fallback.variant})` : ""
+      await Promise.resolve(
+        toast({
+          title: "Model fallback",
+          message: `Using ${fallback.providerID}/${fallback.modelID}${variantLabel}`,
+          variant: "warning",
+          duration: 5000,
+        }),
+      )
+    }
+  }
+
+  if (onApplied) {
+    await Promise.resolve(
+      onApplied({
+        sessionID,
+        providerID: fallback.providerID,
+        modelID: fallback.modelID,
+        variant: fallback.variant,
+      }),
+    )
+  }
+
+  const toastManager = getTaskToastManager()
+  if (toastManager) {
+    const variantLabel = fallback.variant ? ` (${fallback.variant})` : ""
+    toastManager.updateTaskModelBySession(sessionID, {
+      model: `${fallback.providerID}/${fallback.modelID}${variantLabel}`,
+      type: "runtime-fallback",
+    })
+  }
+
+  log("[model-fallback] Applied fallback model: " + JSON.stringify(fallback))
+}