feat(v2): scaffold Tauri 2.x + Svelte 5 project (Phase 1)

- Tauri 2.10 + Svelte 5.45 + TypeScript + Vite 7
- Catppuccin Mocha theme with CSS variables and semantic aliases
- CSS Grid layout: sidebar (260px) + workspace, responsive breakpoints
  for ultrawide (3440px+) and narrow (<1200px)
- Component structure: Layout/, Terminal/, Agent/, Markdown/, Sidebar/
- Svelte 5 stores with $state runes: sessions, agents, layout
- SDK message adapter (abstracts Agent SDK wire format)
- PTY bridge (Tauri IPC wrapper, stubbed for Phase 2)
- Node.js sidecar entry point (stdio NDJSON, stubbed for Phase 3)
- Rust modules: pty, sidecar, watcher, session (stubbed)
- Vite dev server on port 9700
- Build verified: binary + .deb + .rpm + AppImage all produced

v2/src/lib/adapters/pty-bridge.ts

@@ -0,0 +1,30 @@
+// PTY Bridge — IPC wrapper for Rust PTY backend
+// Phase 2: terminal spawn, resize, input/output streaming
+
+export interface PtyOptions {
+  shell?: string;
+  cwd?: string;
+  env?: Record<string, string>;
+  cols?: number;
+  rows?: number;
+}
+
+/**
+ * Spawn a new PTY session via Tauri IPC.
+ * Phase 2: implement with @tauri-apps/api invoke
+ */
+export async function spawnPty(_options: PtyOptions): Promise<string> {
+  throw new Error('Not implemented — Phase 2');
+}
+
+export async function writePty(_id: string, _data: string): Promise<void> {
+  throw new Error('Not implemented — Phase 2');
+}
+
+export async function resizePty(_id: string, _cols: number, _rows: number): Promise<void> {
+  throw new Error('Not implemented — Phase 2');
+}
+
+export async function killPty(_id: string): Promise<void> {
+  throw new Error('Not implemented — Phase 2');
+}

v2/src/lib/adapters/sdk-messages.ts

@@ -0,0 +1,25 @@
+// SDK Message Adapter — insulates UI from Claude Agent SDK wire format changes
+// This is the ONLY place that knows SDK internals.
+// Phase 3: full implementation
+
+export interface AgentMessage {
+  id: string;
+  type: 'text' | 'tool_call' | 'tool_result' | 'subagent_spawn' | 'subagent_stop' | 'status' | 'cost' | 'unknown';
+  parentId?: string;
+  content: unknown;
+  timestamp: number;
+}
+
+/**
+ * Adapt a raw SDK message to our internal format.
+ * When SDK changes wire format, only this function needs updating.
+ */
+export function adaptSDKMessage(raw: Record<string, unknown>): AgentMessage {
+  // Phase 3: implement based on actual SDK message types
+  return {
+    id: (raw.id as string) ?? crypto.randomUUID(),
+    type: 'unknown',
+    content: raw,
+    timestamp: Date.now(),
+  };
+}

v2/src/lib/components/Layout/PaneContainer.svelte

@@ -0,0 +1,54 @@
+<script lang="ts">
+  import type { Snippet } from 'svelte';
+
+  interface Props {
+    title: string;
+    children: Snippet;
+  }
+
+  let { title, children }: Props = $props();
+</script>
+
+<div class="pane-container">
+  <div class="pane-header">
+    <span class="pane-title">{title}</span>
+  </div>
+  <div class="pane-content">
+    {@render children()}
+  </div>
+</div>
+
+<style>
+  .pane-container {
+    display: flex;
+    flex-direction: column;
+    background: var(--bg-secondary);
+    border-radius: var(--border-radius);
+    overflow: hidden;
+    border: 1px solid var(--border);
+  }
+
+  .pane-header {
+    height: var(--pane-header-height);
+    display: flex;
+    align-items: center;
+    padding: 0 10px;
+    background: var(--bg-tertiary);
+    border-bottom: 1px solid var(--border);
+    flex-shrink: 0;
+  }
+
+  .pane-title {
+    font-size: 12px;
+    font-weight: 500;
+    color: var(--text-secondary);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+
+  .pane-content {
+    flex: 1;
+    overflow: auto;
+  }
+</style>

v2/src/lib/components/Layout/PaneHeader.svelte

@@ -0,0 +1,44 @@
+<script lang="ts">
+  interface Props {
+    title: string;
+    status?: 'idle' | 'running' | 'error' | 'done';
+  }
+
+  let { title, status = 'idle' }: Props = $props();
+</script>
+
+<div class="pane-header">
+  <span class="pane-title">{title}</span>
+  {#if status !== 'idle'}
+    <span class="status-indicator {status}">{status}</span>
+  {/if}
+</div>
+
+<style>
+  .pane-header {
+    height: var(--pane-header-height);
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    padding: 0 10px;
+    background: var(--bg-tertiary);
+    border-bottom: 1px solid var(--border);
+    flex-shrink: 0;
+  }
+
+  .pane-title {
+    font-size: 12px;
+    font-weight: 500;
+    color: var(--text-secondary);
+  }
+
+  .status-indicator {
+    font-size: 10px;
+    padding: 2px 6px;
+    border-radius: 3px;
+  }
+
+  .status-indicator.running { color: var(--ctp-blue); }
+  .status-indicator.error { color: var(--ctp-red); }
+  .status-indicator.done { color: var(--ctp-green); }
+</style>

v2/src/lib/components/Layout/TilingGrid.svelte

@@ -0,0 +1,58 @@
+<script lang="ts">
+  import PaneContainer from './PaneContainer.svelte';
+
+  // Phase 2: dynamic pane management, resize, presets
+  // For now: single empty pane as placeholder
+</script>
+
+<div class="tiling-grid">
+  <PaneContainer title="Welcome">
+    <div class="welcome">
+      <h1>BTerminal v2</h1>
+      <p>Claude Agent Mission Control</p>
+      <div class="status">
+        <span class="badge">Phase 1 — Scaffold</span>
+      </div>
+    </div>
+  </PaneContainer>
+</div>
+
+<style>
+  .tiling-grid {
+    display: grid;
+    grid-template-columns: 1fr;
+    grid-template-rows: 1fr;
+    gap: var(--pane-gap);
+    height: 100%;
+    padding: var(--pane-gap);
+  }
+
+  .welcome {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    height: 100%;
+    gap: 8px;
+    color: var(--text-muted);
+  }
+
+  .welcome h1 {
+    font-size: 24px;
+    font-weight: 700;
+    color: var(--text-primary);
+  }
+
+  .welcome p {
+    font-size: 14px;
+  }
+
+  .badge {
+    background: var(--bg-surface);
+    color: var(--accent);
+    padding: 4px 12px;
+    border-radius: var(--border-radius);
+    font-size: 12px;
+    margin-top: 8px;
+  }
+</style>

v2/src/lib/components/Sidebar/SessionList.svelte

@@ -0,0 +1,39 @@
+<script lang="ts">
+  // Phase 4: session CRUD, groups, types
+</script>
+
+<div class="session-list">
+  <div class="header">
+    <h2>Sessions</h2>
+  </div>
+  <div class="empty-state">
+    <p>No sessions yet.</p>
+    <p class="hint">Phase 2 will add terminal sessions.</p>
+  </div>
+</div>
+
+<style>
+  .session-list {
+    padding: 12px;
+  }
+
+  .header h2 {
+    font-size: 14px;
+    font-weight: 600;
+    color: var(--text-primary);
+    margin-bottom: 12px;
+  }
+
+  .empty-state {
+    color: var(--text-muted);
+    font-size: 12px;
+    text-align: center;
+    padding: 24px 0;
+  }
+
+  .hint {
+    margin-top: 4px;
+    font-size: 11px;
+    color: var(--ctp-overlay0);
+  }
+</style>

v2/src/lib/stores/agents.ts

@@ -0,0 +1,34 @@
+// Agent tracking state — Svelte 5 runes
+// Phase 3: SDK agent lifecycle, subagent tree
+
+export type AgentStatus = 'idle' | 'running' | 'thinking' | 'waiting' | 'done' | 'error';
+
+export interface AgentState {
+  id: string;
+  sessionId: string;
+  parentId?: string;
+  status: AgentStatus;
+  model?: string;
+  costUsd?: number;
+  tokensIn?: number;
+  tokensOut?: number;
+}
+
+let agents = $state<AgentState[]>([]);
+
+export function getAgents() {
+  return agents;
+}
+
+export function getAgentTree(rootId: string): AgentState[] {
+  const result: AgentState[] = [];
+  const root = agents.find(a => a.id === rootId);
+  if (!root) return result;
+
+  result.push(root);
+  const children = agents.filter(a => a.parentId === rootId);
+  for (const child of children) {
+    result.push(...getAgentTree(child.id));
+  }
+  return result;
+}

v2/src/lib/stores/layout.ts

@@ -0,0 +1,28 @@
+// Layout state management — Svelte 5 runes
+// Phase 2: pane positions, resize, presets
+
+export type LayoutPreset = '1-col' | '2-col' | '3-col' | '2x2' | 'master-stack';
+
+export interface PaneState {
+  id: string;
+  sessionId: string;
+  row: number;
+  col: number;
+  rowSpan: number;
+  colSpan: number;
+}
+
+let activePreset = $state<LayoutPreset>('1-col');
+let panes = $state<PaneState[]>([]);
+
+export function getActivePreset() {
+  return activePreset;
+}
+
+export function setPreset(preset: LayoutPreset) {
+  activePreset = preset;
+}
+
+export function getPanes() {
+  return panes;
+}

v2/src/lib/stores/sessions.ts

@@ -0,0 +1,26 @@
+// Session state management — Svelte 5 runes
+// Phase 4: full session CRUD, persistence
+
+export type SessionType = 'terminal' | 'agent' | 'markdown';
+
+export interface Session {
+  id: string;
+  type: SessionType;
+  title: string;
+  createdAt: number;
+}
+
+// Reactive session list
+let sessions = $state<Session[]>([]);
+
+export function getSessions() {
+  return sessions;
+}
+
+export function addSession(session: Session) {
+  sessions.push(session);
+}
+
+export function removeSession(id: string) {
+  sessions = sessions.filter(s => s.id !== id);
+}

v2/src/lib/styles/catppuccin.css

@@ -0,0 +1,52 @@
+/* Catppuccin Mocha — https://catppuccin.com/palette */
+:root {
+  --ctp-rosewater: #f5e0dc;
+  --ctp-flamingo: #f2cdcd;
+  --ctp-pink: #f5c2e7;
+  --ctp-mauve: #cba6f7;
+  --ctp-red: #f38ba8;
+  --ctp-maroon: #eba0ac;
+  --ctp-peach: #fab387;
+  --ctp-yellow: #f9e2af;
+  --ctp-green: #a6e3a1;
+  --ctp-teal: #94e2d5;
+  --ctp-sky: #89dceb;
+  --ctp-sapphire: #74c7ec;
+  --ctp-blue: #89b4fa;
+  --ctp-lavender: #b4befe;
+  --ctp-text: #cdd6f4;
+  --ctp-subtext1: #bac2de;
+  --ctp-subtext0: #a6adc8;
+  --ctp-overlay2: #9399b2;
+  --ctp-overlay1: #7f849c;
+  --ctp-overlay0: #6c7086;
+  --ctp-surface2: #585b70;
+  --ctp-surface1: #45475a;
+  --ctp-surface0: #313244;
+  --ctp-base: #1e1e2e;
+  --ctp-mantle: #181825;
+  --ctp-crust: #11111b;
+
+  /* Semantic aliases */
+  --bg-primary: var(--ctp-base);
+  --bg-secondary: var(--ctp-mantle);
+  --bg-tertiary: var(--ctp-crust);
+  --bg-surface: var(--ctp-surface0);
+  --bg-surface-hover: var(--ctp-surface1);
+  --text-primary: var(--ctp-text);
+  --text-secondary: var(--ctp-subtext1);
+  --text-muted: var(--ctp-overlay1);
+  --border: var(--ctp-surface1);
+  --accent: var(--ctp-blue);
+  --accent-hover: var(--ctp-sapphire);
+  --success: var(--ctp-green);
+  --warning: var(--ctp-yellow);
+  --error: var(--ctp-red);
+
+  /* Layout */
+  --sidebar-width: 260px;
+  --right-panel-width: 380px;
+  --pane-header-height: 32px;
+  --pane-gap: 2px;
+  --border-radius: 4px;
+}