fix(vscode): fix context usage calculation and compact error handling

- Add limit field to ProviderModel types to match actual server response
  (server sends limit.context, not contextLength)
- Use limit.context for context usage percentage with contextLength fallback
- Show task header when messages exist, even before title is generated
- Validate model selection before compact instead of hardcoding kilo fallback

packages/kilo-vscode/src/KiloProvider.ts

@@ -523,9 +523,18 @@ export class KiloProvider implements vscode.WebviewViewProvider {
       return
     }
 
+    if (!providerID || !modelID) {
+      console.error("[Kilo New] KiloProvider: No model selected for compact")
+      this.postMessage({
+        type: "error",
+        message: "No model selected. Connect a provider to compact this session.",
+      })
+      return
+    }
+
     try {
       const workspaceDir = this.getWorkspaceDirectory()
-      await this.httpClient.summarize(target, providerID || "kilo", modelID || "kilo/auto", workspaceDir)
+      await this.httpClient.summarize(target, providerID, modelID, workspaceDir)
     } catch (error) {
       console.error("[Kilo New] KiloProvider: Failed to compact session:", error)
       this.postMessage({

packages/kilo-vscode/src/services/cli-backend/types.ts

@@ -100,6 +100,8 @@ export interface ProviderModel {
   contextLength?: number
   releaseDate?: string
   latest?: boolean
+  // Actual shape returned by the server (Provider.Model)
+  limit?: { context: number; input?: number; output: number }
 }
 
 // Provider definition

packages/kilo-vscode/webview-ui/src/components/chat/TaskHeader.tsx

@@ -14,7 +14,7 @@ export const TaskHeader: Component = () => {
 
   const title = createMemo(() => session.currentSession()?.title)
   const hasMessages = createMemo(() => session.messages().length > 0)
-  const visible = createMemo(() => !!(title() && hasMessages()))
+  const visible = createMemo(() => hasMessages())
   const busy = createMemo(() => session.status() === "busy")
 
   const cost = createMemo(() => {

packages/kilo-vscode/webview-ui/src/context/session.tsx

@@ -442,7 +442,8 @@ export const SessionProvider: ParentComponent = (props) => {
       if (total === 0) continue
       const sel = selected()
       const model = sel ? provider.findModel(sel) : undefined
-      const percentage = model?.contextLength ? Math.round((total / model.contextLength) * 100) : null
+      const limit = model?.limit?.context ?? model?.contextLength
+      const percentage = limit ? Math.round((total / limit) * 100) : null
       return { tokens: total, percentage }
     }
     return undefined

packages/kilo-vscode/webview-ui/src/types/messages.ts

@@ -157,6 +157,8 @@ export interface ProviderModel {
   contextLength?: number
   releaseDate?: string
   latest?: boolean
+  // Actual shape returned by the server (Provider.Model)
+  limit?: { context: number; input?: number; output: number }
 }
 
 export interface Provider {