Move SKILL.md to .github/skills/ and add skill metadata

[Copilot]

The SKILL.md file in docs/ was a developer guide that needed to be relocated to .github/skills/ and converted to a proper skill file format.

Changes

• Relocated file: docs/SKILL.md → .github/skills/developer-guide/SKILL.md
• Added skill metadata frontmatter:

  ---
  name: developer-guide
  description: Comprehensive guide to technical skills, knowledge areas, and competencies required for BitSleuth Wallet development. Covers React Native/Expo mobile development, Bitcoin protocol expertise, cryptography, security best practices, and platform-specific knowledge for building a professional-grade Bitcoin wallet.
  ---

• Updated internal references: Adjusted relative paths to documentation files to reflect new location in skill hierarchy

The file now matches the structure of existing skills (frontend-design, webapp-testing) with proper YAML frontmatter.

Original prompt

Can you move the SKILL.md in docs to .github/skills/*** some appropriate folder name ***/

Make sure the skill file is like the others in this location having everything required to be a skill file? Include name and description boxes.

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