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, 7 insertions, 2 deletions

diff --git a/src/features/chat/index.ts b/src/features/chat/index.ts
index 1596c53..c120916 100644
--- a/src/features/chat/index.ts
+++ b/src/features/chat/index.ts
@@ -1,5 +1,10 @@
-export type { RenderedChunk, RenderGroup, ToolBatchEntry } from "../../core/chunks";
-export { groupRenderedChunks } from "../../core/chunks";
+export type {
+	ProviderRetryView,
+	RenderedChunk,
+	RenderGroup,
+	ToolBatchEntry,
+} from "../../core/chunks";
+export { groupRenderedChunks, viewProviderRetry } from "../../core/chunks";
 export type { TurnMetricsEntry } from "../../core/metrics";
 export type { ChatTransport, HistorySync, HistoryWindow, MetricsSync } from "./ports";
 export type {