Add pluggable wallet onboarding paths

[jwahdatehagh]

What

• Add connectorFilter to EvmConnect with backward-compatible all, external, and in-app modes.
• Add initialStep to EvmInAppWalletSetup so consumers can enter the create or restore path directly.
• Pass those controls through EvmConnectDialog, EvmConnectAuth, and EvmConnectAuthDialog.
• Bubble a back event through the connect/auth wrappers so the host app can own the preceding choice screen.
• Document the split onboarding composition and add a minor changeset for @1001-digital/components.evm.

Why

The 11x11 onboarding needs to ask whether someone already has a wallet before showing wallet UI. Existing-wallet users should see external connectors only, while new-wallet users should enter in-app account creation directly. Today those paths are hard-coded into one connector list and the in-app component adds a second internal chooser, forcing app-specific duplication or DOM-level filtering.

Impact

Defaults remain connectorFilter="all" and initialStep="choose", so current consumers keep the existing behavior. Apps can now wire their own question or other onboarding shell around the shared components without copying wallet creation logic.

This touches the same in-app setup surface as draft #88. The API is intentionally state-agnostic so it can be retained when that internal vault rewrite is rebased.

Checks

• pnpm --filter @1001-digital/layers.evm typecheck
• pnpm --filter @1001-digital/layers.evm build
• pnpm test (11 passed)
• pnpm docs:build
• Prettier check on all changed files
• git diff --check

Repository-wide pnpm typecheck and pnpm format:check are not clean on master: the former stops in layers.base on its existing .ts import/configuration error (and this worktree also reported existing missing playground dependencies), while the latter reports existing drift in CHANGELOG.md and pnpm-lock.yaml. The targeted EVM checks above pass.