docs: fix stale milla-jovovich org URLs in website and plugin manifests (#787)

Follow-up to #766 which covers version.py, pyproject.toml, README,
CHANGELOG, and CONTRIBUTING. These 11 files still had the old org
name in URLs:

- website/ (VitePress config + 6 docs pages)
- .claude-plugin/ (plugin.json repository, README marketplace command)
- .codex-plugin/ (plugin.json URLs, README links)

Author name fields are intentionally unchanged.

website/reference/contributing.md

@@ -5,7 +5,7 @@ PRs welcome. MemPalace is open source and we welcome contributions of all sizes
 ## Getting Started
 
 ```bash
-git clone https://github.com/milla-jovovich/mempalace.git
+git clone https://github.com/MemPalace/mempalace.git
 cd mempalace
 pip install -e ".[dev]"
 ```
@@ -53,7 +53,7 @@ See [Benchmarks](/reference/benchmarks) for data download instructions.
 
 ## Good First Issues
 
-Check the [Issues](https://github.com/milla-jovovich/mempalace/issues) tab:
+Check the [Issues](https://github.com/MemPalace/mempalace/issues) tab:
 
 - **New chat formats** — add import support for Cursor, Copilot, or other AI tool exports
 - **Room detection** — improve pattern matching in `room_detector_local.py`
@@ -73,8 +73,8 @@ If you're planning a significant change, open an issue first. Key principles:
 ## Community
 
 - [Discord](https://discord.com/invite/ycTQQCu6kn)
-- [GitHub Issues](https://github.com/milla-jovovich/mempalace/issues) — bug reports and feature requests
-- [GitHub Discussions](https://github.com/milla-jovovich/mempalace/discussions) — questions and ideas
+- [GitHub Issues](https://github.com/MemPalace/mempalace/issues) — bug reports and feature requests
+- [GitHub Discussions](https://github.com/MemPalace/mempalace/discussions) — questions and ideas
 
 ## License