docs: add CDX summary (#1404)

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### Description

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A clear and concise summary of the change and which issue (if any) it
fixes. Should also include relevant motivation and context.

Resolves or fixes issue: <!-- ✍️ Add GitHub issue number in format
`#0000` or `none` -->

### AI Tool Disclosure

- [x] My contribution does not include any AI-generated content
- [ ] My contribution includes AI-generated content, as disclosed below:
  - AI Tools: `[e.g. GitHub CoPilot, ChatGPT, JetBrains Junie etc.]`
- LLMs and versions: `[e.g. GPT-4.1, Claude Haiku 4.5, Gemini 2.5 Pro
etc.]`
- Prompts: `[Summarize the key prompts or instructions given to the AI
tools]`

### Affirmation

- [x] My code follows the
[CONTRIBUTING.md](https://github.com/CycloneDX/cyclonedx-javascript-library/blob/main/CONTRIBUTING.md)
guidelines

---------

Signed-off-by: Jan Kowalleck <jan.kowalleck@gmail.com>

Author: jkowalleck

README.md

@@ -13,7 +13,10 @@
 
 ----
 
-Core functionality of [_CycloneDX_][link_website] for _JavaScript_ (_Node.js_ or _WebBrowsers_),
+OWASP [CycloneDX][link_website] is a full‑stack Bill of Materials (BOM) and system‑transparency standard
+that provides deep visibility into software, services, hardware, and AI components, enabling advanced supply‑chain security and cyber‑risk reduction.
+
+This package provides functionality of _CycloneDX_ for _JavaScript_ (_Node.js_ or _WebBrowsers_),
 written in _TypeScript_ and compiled for the target.
 
 > [!NOTE]