feat(v0.1.5): Always-on Registration + Scrollable Language Selector

## Registration (Breaking Change)
- Remove ACCOUNT_REGISTRATION restriction on Register page
- Login page always shows Register link
- Registration behavior now matches upstream v0.17.0

## UI Improvements
- Language selector dropdown: add max-height (320px) + overflow-y: auto
- Prevents UI overflow when 65+ languages are displayed

## Documentation
- New docs/faq.md with common questions
- Simplified README quick start (remove ACCOUNT_REGISTRATION from examples)
- Updated getting-started.md with folder initialization guide

## Build Verification
- bun run build: PASSED
- Docker build: PASSED
- TypeScript: PASSED

src/components/languageSelector.tsx

@@ -51,7 +51,7 @@ export const LanguageSelector = ({
       <ul
         id="language-dropdown"
         class={`
-          absolute right-0 top-full z-50 mt-2 hidden min-w-[140px] flex-col overflow-hidden rounded
+          absolute right-0 top-full z-50 mt-2 hidden min-w-[160px] max-h-[320px] flex-col overflow-y-auto rounded
           border border-neutral-700 bg-neutral-800 shadow-lg
         `}
         role="menu"