Fix Node provider watch path handling and remove main test entry
- Node provider: detect at start whether the watched path is a file or directory (fs.stat) and build fullPath accordingly so watching a single file does not incorrectly join the filename onto the file path.
- Watch callback: ensure events are evaluated against the configured filter using the correct full path.
- Tests: removed test/test.ts (main test entry that previously imported provider test files).
Add SmartFS core library with providers, builders, interfaces, docs, tests and CI
- Add core TypeScript sources and public exports: SmartFs, SmartFsFile, SmartFsDirectory, SmartFsTransaction, SmartFsWatcher and ts/index.ts
- Add two providers: SmartFsProviderNode (Node.js fs/promises + fs.watch) and SmartFsProviderMemory (in-memory implementation used for testing)
- Add provider and type contracts: ISmartFsProvider, IProviderCapabilities and comprehensive mod.types definitions
- Implement transactions with prepare/execute/rollback, atomic writes, Web Streams-based read/write streams, and file watching with debouncing and filters
- Add tests entry (test/test.ts) and test scaffolding for memory and node providers