feat: workspaces shell + cwd-lsp rename + mcp/settings/system-prompt features + app wiring

- workspaces: URL-driven conversation grouping (home listing at /, routing,
  store, http adapter, WorkspaceCard) wired into the App.svelte shell
- rename features/workspace -> features/cwd-lsp (the cwd/lsp status feature)
- new features: mcp (status view), settings (chat-limit field), system-prompt
  (prompt builder), all rendered via the generic surface host
- chat: store + ChatView updates
- tabs: tabs-store updates
- app wiring: ErrorModal (full-screen error surface), app/App.svelte + store.svelte

This commit makes HEAD typecheck clean for the first time: the prior HEAD
(dfe1711) imported features/settings from app/App.svelte but never committed
the feature, so only the full working tree was green.

1 files changed, 11 insertions, 1 deletions

diff --git a/src/features/tabs/tabs.ts b/src/features/tabs/tabs.ts
index 3360d3f..53eda78 100644
--- a/src/features/tabs/tabs.ts
+++ b/src/features/tabs/tabs.ts
@@ -2,6 +2,8 @@ export interface Tab {
 	readonly conversationId: string;
 	readonly model: string;
 	readonly title: string;
+	/** The workspace this tab belongs to (the workspace's URL slug). */
+	readonly workspaceId: string;
 }
 
 export interface TabsState {
@@ -13,7 +15,15 @@ const DEFAULT_TITLE = "New chat";
 const DEFAULT_MAX_TITLE_LENGTH = 40;
 
 export function initialState(persisted?: TabsState): TabsState {
-	if (persisted !== undefined) return persisted;
+	if (persisted !== undefined) {
+		// Migrate tabs persisted before workspaces: assign them to the "default"
+		// workspace (the fallback for conversations with no workspace).
+		const tabs = persisted.tabs.map((t) => {
+			const wid = (t as { workspaceId?: string }).workspaceId;
+			return { ...t, workspaceId: wid ?? "default" };
+		});
+		return { tabs, activeConversationId: persisted.activeConversationId };
+	}
 	return { tabs: [], activeConversationId: null };
 }