fix: restore web terminal multiline paste by reverting scrollback to 10000

- Revert xterm.js scrollback from 0 to 10000; empirical correlation with
  bracketed-paste mode failing (each line submitted as separate command).
- Add temporary browser-console diagnostics to confirm whether xterm receives
  pi's \e[?2004h enable sequence and whether outbound paste is BPM-wrapped.
- Keep CSS scrollbar hiding and wheel-sensitivity 0 so the original scroll-jank
  fix remains effective.

Typecheck: passed (apps/web)

apps/web/src/components/.pi-map.md

@@ -4,22 +4,22 @@ dir: apps/web/src/components
 index: apps/web/src/components/.pi-map.index.md
 
 ## role
-Provides reusable, type-safe React UI components for the web application including layout shells, data display states, iconography, code editing, syntax highlighting, authentication guards, and toast notification rules.
+Package components
 ## files
-- app-shell.tsx | Provides the main application layout shell with navigation, session management, and responsive mobile/desktop views for a React application. | exp: AppShell | dep: react-router-dom, ../api/sessions, ../hooks/use-theme, ../utils/open-session, ../state/auth, ../state/sessions, ../hooks/use-mobile-viewport, ../state/events, ../state/toast, ../state/notifications, ./features/notification/event-toast-bridge, ./features/notification/notification-center, ./icon, ./features/mobile/mobile-nav, ./features/tool/start-tool-fab, ../utils/icons
-- code-editor.tsx | A React component that renders a syntax-highlighted code editor with line numbers using a lightweight editor library. | exp: CodeEditor | dep: react, react-simple-code-editor, ../utils/language
-- data-states.tsx | Defines reusable React components for displaying loading, error, and empty data states in a UI. | exp: LoadingState, ErrorState, EmptyState | dep: ./icon, icon
-- icon.tsx | Provides a centralized, type-safe React component that maps semantic icon names to Phosphor icons with configurable size, weight, color, and accessibility properties. | exp: IconName, IconProps, Icon | dep: react, @phosphor-icons/react
-- loading-overlay.tsx | Renders an accessible loading spinner overlay with optional text label that conditionally displays based on visibility prop | exp: func:LoadingOverlay({ visible, label }: LoadingOverlayProps) | dep: ./icon, icon
-- protected-route.test.tsx | Tests a ProtectedRoute component that guards content based on authentication state | dep: @testing-library/react, react-router-dom, vitest, ./protected-route, ../state/auth
-- protected-route.tsx | A React component that conditionally renders children or redirects to login based on authentication state | exp: ProtectedRoute | dep: react-router-dom, ../state/auth
-- syntax-highlighter.tsx | A React component that renders syntax-highlighted code blocks with optional line numbers, language badge, and copy-to-clipboard functionality. | exp: SyntaxHighlighter | dep: react, ./icon, ../utils/language
-- toast-rules.test.ts | Unit tests for toast notification rules that map instance events to UI categories and severity levels. | dep: vitest, ./toast-rules, ../types/events
-- toast-rules.ts | Maps instance events to toast notifications with deduplication logic to prevent spam. | exp: func:mapEventToCategory(event: InstanceEventPayload) → string, call:event.event.startsWith, func:mapEventToSeverity(event: InstanceEventPayload) → "info" | "warning" | "error" | "success", func:handleEventToast(event: InstanceEventPayload) → void, call:shouldShowToast, call:toast.info, call:toast.success, call:toast.warning, call:toast.error, func:clearToastDedup() → void, call:lastToastTime.clear | dep: ../state/toast, ../types/events, toast, InstanceEventPayload
+- app-shell.tsx | Main application layout shell with responsive navigation, session management, and global state providers for notifications and toasts. | exp: AppShell | dep: react-router-dom, ../api/sessions, ../hooks/use-theme, ../utils/open-session, ../state/auth, ../state/sessions, ../hooks/use-mobile-viewport, ../state/events, ../state/toast, ../state/notifications, ./features/notification/event-toast-bridge, ./features/notification/notification-center, ./icon, ./features/mobile/mobile-nav, ./features/tool/start-tool-fab, ../utils/icons
+- code-editor.tsx | A React component that renders a syntax-highlighting code editor with line numbers using react-simple-code-editor. | exp: CodeEditor | dep: react, react-simple-code-editor, ../utils/language
+- data-states.tsx | Provides reusable UI components for rendering loading, error, and empty data states. | exp: LoadingState, ErrorState, EmptyState | dep: ./icon, Icon
+- icon.tsx | Provides a centralized, type-safe React icon component that maps semantic names to Phosphor icons with configurable sizes, weights, and colors. | exp: IconName, IconProps, Icon | dep: react, @phosphor-icons/react
+- loading-overlay.tsx | Renders an accessible loading overlay with optional text label when visible | exp: func:LoadingOverlay({ visible, label }: LoadingOverlayProps) | dep: ./icon, icon
+- protected-route.test.tsx | Tests a ProtectedRoute component that guards content based on authentication state, showing loading or redirecting to login | dep: @testing-library/react, react-router-dom, vitest, ./protected-route
+- protected-route.tsx | Conditionally renders children or redirects to login based on authentication state | exp: ProtectedRoute | dep: react-router-dom, ../state/auth
+- syntax-highlighter.tsx | A React component that renders syntax-highlighted code with optional line numbers and a copy-to-clipboard button | exp: SyntaxHighlighter | dep: react, ./icon, ../utils/language, React, icon, language utils
+- toast-rules.test.ts | Unit tests for mapping instance events to toast notification categories and severities | dep: vitest, ./toast-rules, ../types/events
+- toast-rules.ts | Maps instance events to toast notifications with deduplication logic | exp: func:mapEventToCategory(event: InstanceEventPayload) → string, call:event.event.startsWith, func:mapEventToSeverity(event: InstanceEventPayload) → "info" | "warning" | "error" | "success", func:handleEventToast(event: InstanceEventPayload) → void, call:shouldShowToast, call:toast.info, call:toast.success, call:toast.warning, call:toast.error, func:clearToastDedup() → void, call:lastToastTime.clear | dep: ../state/toast, ../types/events, toast, InstanceEventPayload
 ## arch
-Follows a component-based architecture with presentational/ui components, separation of concerns (display logic vs. business rules in `.ts` files), test co-location, and centralized abstractions for common patterns like icons and data states.
+Contains 10 files.
 ## tags
-toast, state, react, icon, loading, event, code, editor
+toast, state, icon, react, loading, code, event, editor
 ## symbols
 - LoadingOverlay
 - mapEventToCategory