feat: Initial launch v0.1.0

Initialize `sized` CLI tool with comprehensive features for directory visualization.

Features:
- Fast parallel directory traversal using `rayon`.
- Rich table output with colors and dual units (Binary/Decimal).
- Recursive sizing with depth control (`-d`).
- Filtering by minimum size (`-m`).
- Sorting by name, type, size, or blocks (`--sort`).
- Gitignore integration (`--ignore`).
- Multiple output formats: Text, CSV, JSON (`--format`).
- Export to file functionality (`--save`).
- Shell completion generation (`--completions`).

CHANGELOG.md

@@ -0,0 +1,23 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.1.0] - 2026-01-22
+
+### Added
+- Core directory traversal and size calculation logic.
+- Parallel processing using `rayon` for high performance.
+- Rich table output format using `comfy-table` with colored entries.
+- Recursive depth control via `-d`/`--depth`.
+- Minimum size filtering via `-m`/`--min-size`.
+- Multi-column sorting support (`--sort`).
+- Relative path display by default, with `-f`/`--path-full` override.
+- "Total size" summary with dual units (Binary/Decimal) and block counts.
+- Concurrency control via `-j`/`--threads`.
+- `.gitignore` and `.ignore` file support via `-i`/`--ignore`.
+- Multiple output formats: Text (Table), CSV, JSON (`--format`).
+- Save to file functionality with auto-naming (`--save`).
+- Shell completion generation (`--completions`).