Add extension metadata and screenshots for LNbits UI (#46)

* Add extension metadata and screenshots for LNbits UI

- Update description.md with comprehensive explanation of relay multiplexer
- Add screenshots array to config.json pointing to 1.jpeg and 2.jpeg
- Change short_description to "Nostr relay multiplexer" for clarity
- Create extensions.json with nostrclient-dev entries for testing
- Add CLAUDE.md for future Claude Code instances

Fixes #41

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Co-Authored-By: Claude <noreply@anthropic.com>

* Change extension name to 'Nostr Client Dev'

Rename extension from 'Nostr Client' to 'Nostr Client Dev' to distinguish from the official extension.

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Co-Authored-By: Claude <noreply@anthropic.com>

* FIX: Ensure valid json

Wrap extensions array in object with "featured" and "extensions" keys to match LNbits Manifest format. This fixes the "1 validation error for Manifest" issue.

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Co-Authored-By: Claude <noreply@anthropic.com>

* Update config.json format for LNbits UI display

- Change name to "Nostr Client Dev" to match extensions.json
- Replace "screenshots" with "images" array using proper format
- Add "description_md" URL for full description display

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Co-Authored-By: Claude <noreply@anthropic.com>

* Crop screenshot 1 to match height of screenshot 2

Crop bottom of 1.jpeg to make both screenshots the same height (1557px) for consistent display in LNbits UI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Remove headings from description.md

Remove markdown headings for cleaner display in LNbits extension UI.

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Co-Authored-By: Claude <noreply@anthropic.com>

* Change name back to 'Nostr Client' in config.json

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Delete CLAUDE.md

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Vlad Stan <stan.v.vlad@gmail.com>

config.json

@@ -1,8 +1,17 @@
 {
   "name": "Nostr Client",
+  "short_description": "Nostr relay multiplexer",
   "version": "1.1.0",
-  "short_description": "Nostr client for extensions",
   "tile": "/nostrclient/static/images/nostr-bitcoin.png",
   "contributors": ["calle", "motorina0", "dni"],
-  "min_lnbits_version": "1.0.0"
+  "min_lnbits_version": "1.0.0",
+  "images": [
+    {
+      "uri": "https://raw.githubusercontent.com/lnbits/nostrclient/add-extension-metadata/static/images/1.jpeg"
+    },
+    {
+      "uri": "https://raw.githubusercontent.com/lnbits/nostrclient/add-extension-metadata/static/images/2.jpeg"
+    }
+  ],
+  "description_md": "https://raw.githubusercontent.com/lnbits/nostrclient/add-extension-metadata/description.md"
 }