feat: discussion feature

[StewartJingga]

Is your feature request related to a problem? Please describe.
I want to create issues on a resource so that other users can see it.

Describe the solution you'd like

1. CRUD Issue apis for a resource

[mabdh]

Use cases

Discussion

• Create a discussion
• Get a discussion
• List discussion
• Update a discussion
• Upvote discussion (out of scope)
• Pinning/Unpinning discussions (out of scope)

Discussion Comments

• List discussion comments
• Get a discussion comment
• Create discussion comment
• Update discussion comment
• Delete discussion comment
• Upvote discussion comment (out of scope)

Discussion Labels

• List labels of a discussion

Users' Discussions

• List assigned discussion of a user

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With use cases mentioned above, we could generalize it into discussions by defining it into multiple types.

Discussion Property

• Title
• Body
• State
• Assignees (nullable, array of string)
• Assets (nullable, array of string)
• Owner (not null)
• Labels (nullable, array of string)
• Type (int)

Discussion Types

• Issues
  • states
    • Unknown: enum 0
    • Open: enum 1
    • Closed: enum 2
• Q&A
  • states
    • Unknown: enum 0
    • Unanswered: enum 1
    • Answered: enum 2
  • Comments can be marked as an answer (out of scope)
  • Suggest answer (out of scope)
  • Vote best answer (out of scope)
• Open-ended questions
  • No states

Users discussion

• Return discussion in user context
• Owned, assigned

Comments

• Comment belongs to the discussion
• Discussion could have multiple comments
• Comments could have replies which is another comments (out of scope)
• Reply comment could not be upvoted (out of scope)