docs(user-guide): document jira issue attachment transfer and ocr

[plumjohan]

Summary

• Added §5 "Create Issue with Attachment Transfer" to the Jira tool documentation, covering the new opt-in attachment copy and image OCR capabilities
• Added "Issue Cloning with Attachment Transfer" use case to the Use Cases section

What changed

Both attachment transfer and image text extraction (OCR) are opt-in — the tool does nothing by default. Users must explicitly request each capability:

• Copy attachments: ask the assistant to copy attachments from a source ticket when creating a new one (copy_attachments)
• Image OCR: ask the assistant to extract text from image attachments; result is posted as a comment on the new issue (ocr_images / run_ocr)

Quality Checks

• npm run check passes (typecheck + lint + commitlint)
• No MDX compilation errors
• No raw angle brackets (<text> must be `<text>`)
• Sidebar references document IDs (not filenames)
• Commit messages follow Conventional Commits
• No secrets or credentials in documentation

[codemie-ai]

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It will be automatically closed no earlier than 2026-09-23 (UTC) (~6 more days).

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