feat: add TypeScript installation wizard with @clack/prompts TUI

Replace bash mosaic-init with a modern 9-stage wizard:
- SOUL.md identity, USER.md profile, TOOLS.md configuration
- Runtime detection (Claude, Codex, OpenCode) + MCP setup
- Skills catalog with categorized selection
- Quick Start and Advanced modes
- HeadlessPrompter for --non-interactive and CI usage
- ConfigService abstraction layer for future DB migration
- Bundled as single dist/mosaic-wizard.mjs via tsdown
- mosaic init now prefers wizard when Node.js is available
- 30 tests covering stages, templates, and integration

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/prompter/interface.ts

@@ -0,0 +1,56 @@
+export interface SelectOption<T = string> {
+  value: T;
+  label: string;
+  hint?: string;
+}
+
+export interface MultiSelectOption<T = string> extends SelectOption<T> {
+  selected?: boolean;
+}
+
+export interface ProgressHandle {
+  update(message: string): void;
+  stop(message?: string): void;
+}
+
+export interface WizardPrompter {
+  intro(message: string): void;
+  outro(message: string): void;
+  note(message: string, title?: string): void;
+  log(message: string): void;
+  warn(message: string): void;
+
+  text(opts: {
+    message: string;
+    placeholder?: string;
+    defaultValue?: string;
+    validate?: (value: string) => string | void;
+  }): Promise<string>;
+
+  confirm(opts: {
+    message: string;
+    initialValue?: boolean;
+  }): Promise<boolean>;
+
+  select<T>(opts: {
+    message: string;
+    options: SelectOption<T>[];
+    initialValue?: T;
+  }): Promise<T>;
+
+  multiselect<T>(opts: {
+    message: string;
+    options: MultiSelectOption<T>[];
+    required?: boolean;
+  }): Promise<T[]>;
+
+  groupMultiselect<T>(opts: {
+    message: string;
+    options: Record<string, MultiSelectOption<T>[]>;
+    required?: boolean;
+  }): Promise<T[]>;
+
+  spinner(): ProgressHandle;
+
+  separator(): void;
+}