Implement `--update` and `--update-all` flags for `rafters add`

[ssilvius]

Goal

Add --update and --update-all flags to rafters add so users can pull the latest registry versions of installed components without manually specifying --overwrite for each one.

Exact Implementation Requirements

Required Interface/Class Structure

// Updated AddOptions
interface AddOptions {
  overwrite?: boolean;
  update?: boolean;     // re-fetch named components from registry
  updateAll?: boolean;  // re-fetch ALL installed components from registry
  list?: boolean;
  registryUrl?: string;
  agent?: boolean;
}

// New field in RaftersConfig (init.ts)
interface RaftersConfig {
  framework: Framework;
  componentsPath: string;
  primitivesPath: string;
  cssPath: string | null;
  shadcn: boolean;
  exports: ExportConfig;
  installedComponents?: string[];  // NEW: tracks what was installed via `add`
}

Behavior Requirements

Track installed components:

• When add successfully installs a component, append its name to installedComponents in config.rafters.json
• De-duplicate the list (Set-based)
• Include primitive dependencies in the list (they are installed too)

rafters add button --update:

• Equivalent to rafters add button --overwrite but reads more clearly as intent
• Fetches latest from registry, overwrites existing files
• Updates installedComponents list

rafters add --update-all:

• Reads installedComponents from config.rafters.json
• Re-fetches and overwrites every listed component from the registry
• No component names required on the CLI when using --update-all
• If installedComponents is empty or missing, error with: "No installed components found. Use 'rafters add <component>' to install first."
• Reports what was updated and what was unchanged (content-identical)

No versioning:

• Components are always latest from registry (shadcn model: source code you own)
• No version tracking, no pinning, no diffing -- just re-fetch and overwrite
• The installedComponents list is purely "what names were installed", not "what version"

Error Handling

• --update-all with no config file: "No rafters config found. Run 'rafters init' first."
• --update-all with empty installedComponents: "No installed components found. Use 'rafters add <component>' to install first."
• --update without component names: same error as current add with no args
• --update and --update-all together: --update-all takes precedence, ignore component args
• Registry fetch failure: existing error handling applies

Acceptance Criteria

Functional Tests Required

// Track installed components
test('add records component in installedComponents', async () => {
  await add(['button'], { overwrite: false });
  const config = JSON.parse(await readFile(configPath, 'utf-8'));
  expect(config.installedComponents).toContain('button');
});

// --update overwrites existing
test('--update re-fetches and overwrites existing component', async () => {
  await add(['button'], {});
  await add(['button'], { update: true });
  // Should succeed without error (no "already exists" error)
});

// --update-all refreshes all installed
test('--update-all refreshes all installed components', async () => {
  await add(['button', 'input'], {});
  await add([], { updateAll: true });
  // Should re-fetch both button and input
});

// --update-all with nothing installed
test('--update-all errors when no components installed', async () => {
  await add([], { updateAll: true });
  expect(process.exitCode).toBe(1);
});

TypeScript Requirements

• TypeScript 5.9.3 strict mode enabled
• No any types anywhere (Biome enforced)
• No .forEach() - use for...of loops
• No .then() chains - use async/await only
• All external data validated with Zod schemas

Build Requirements

• All existing Biome rules enforced
• pnpm preflight must pass

What NOT to Include

• Component versioning or pinning (not needed -- always latest)
• Diffing installed vs registry (future consideration)
• Interactive component selection for update (separate issue)
• Migration or changelog between component versions (out of scope)

File Locations

• Implementation: packages/cli/src/commands/add.ts
• Config type update: packages/cli/src/commands/init.ts (RaftersConfig interface)
• Unit Tests: packages/cli/test/add.test.ts
• Types: packages/cli/src/registry/types.ts (if schema changes needed)

Integration Requirements

Dependencies

• Reads/writes config.rafters.json (already used by init)
• Uses existing RegistryClient for fetching
• No new package dependencies

Usage Examples

# Install a component (now also tracks it)
rafters add button

# Update a specific component to latest
rafters add button --update

# Update all installed components to latest
rafters add --update-all

# Agent mode works too
rafters add --update-all --agent

Success Criteria

• rafters add <name> records installed components in config
• rafters add <name> --update re-fetches and overwrites
• rafters add --update-all refreshes all installed components
• Existing --overwrite behavior unchanged
• All functional tests pass
• TypeScript compiles without errors
• pnpm preflight passes

This issue is complete when: rafters add --update-all successfully re-fetches and overwrites all previously installed components from the registry, and the installed component list persists across CLI invocations.

Context & References

• Current --overwrite behavior: always re-fetches from registry, but requires flag to write over existing files
• shadcn model: no versioning, components are source code you own
• RaftersConfig in packages/cli/src/commands/init.ts (line 78)
• AddOptions in packages/cli/src/commands/add.ts