docs(UPIIS-47): UPI Issuance onboarding developer docs + OpenAPI refe…

[Anindya-Pandey]

UPI Issuance — onboarding developer docs + OpenAPI API reference

Adds the client-facing developer documentation for the UPI Issuance onboarding surface, plus the OpenAPI spec that powers its interactive API
reference.

Jira: UPIIS-47 (https://setu.atlassian.net/browse/UPIIS-47)

What's included

Guide pages (content/payments/upi-issuance/)

• Overview, Quickstart, API envelope
• Device binding, OTP verification, VPA management, Programs, Payee blocklist
• Testing on the QA env, API reference

API reference (api-references/payments/upi-issuance/upi-issuance.json)

• OpenAPI generated from the tpapapi goa DSL, with client-facing polish:
  • Human-readable operation summaries; sections ordered to match the docs (Device binding → OTP → VPA management → Programs → Payee blocklist)
  • Internal endpoints (/webhooks/vmn, /tpap-config) excluded from the reference
  • Per-operation error-code enums + examples (each status lists only the codes it can actually return)
  • Consistent conventions across docs and refs: deviceId, mobile (with country code), idempotencyKey (plain key), cursor/id as ULIDs, full-VPA
    (prefix@handle) params, use-case-framed otpRequired

Nav registration: content/endpoints.json, content/menuItems.json, content/redirects.json

[github-actions]

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Edit an existing content (MDX) page

Checklist

• Review changes using the MDX preview option
• If the length of content >15000 chars, use the Content preview portal to view changes
• If a redirect is needed to the existing page, add a key, value pair in redirects.json

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Edit an existing API reference page

Checklist

• Use the Content preview portal to view changes
• API reference is in JSON format (OpenAPI or Swagger)

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Add a new content (MDX) page

Checklist

• Create a .mdx file with the path as its name in the content folder
• Add frontmatter with all the metadata
• Review the order of items in Sidebar using the Sidebar preview option
• Review changes using the MDX preview option
• If the length of content >15000 chars, use the Content preview portal to view changes
• Created a folder with the same name, if any children were to be added to the page
• Once all changes are done, update the menu items by using the Menu Items option
• Add a key, and value pair in redirects.json if you wish to have a redirect to the new page

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Add a new API reference page

Checklist

• Create a .json file with the product path as its name
• Create an api-reference.mdx file in the respective product folder inside content folder
• Add frontmatter with all the metadata
• Review the order of items in Sidebar using the Sidebar preview option
• Add API reference in JSON format (OpenAPI or Swagger) into created .json file.
• Used the Content preview portal to view changes
• Once all changes are done, update the menu items by using the Menu Items option