Feat/thread summarizer

[skkuwari-alt]

Solves Issue: #19

Summary
This PR introduces a fully functional Thread Summarizer plugin for NodeBB.

It provides an /api/thread-summarizer/v2/:tid REST route that generates concise summaries of forum topics using the OpenAI API.

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Features Implemented

• Adds new API route: /api/thread-summarizer/v2/:tid

• Integrates OpenAI API (gpt-4o-mini) for summarization

• Includes environment variable controls:

  • OPENAI_API_KEY – required for real summaries
    Each user must set their own OpenAI API key in the environment before running the server.
  • TS_STUB=1 – enables offline testing (returns fake summaries)

• Adds an LRU cache (10-minute expiry) to avoid redundant API calls

• Implements a per-user cooldown (30 seconds) to prevent spam

• Handles permission checks via privileges.topics.can

• Returns clean JSON responses for both cached and fresh summaries

• Uses posts.getPostsByPids to gather thread content

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How It Works

1. The topic page includes a “Summarize this topic” button.
2. The server collects up to 40 posts and constructs a summarization prompt.
3. The OpenAI API generates 5–8 bullet points and a one-line TL;DR.
4. The summary is cached and returned as JSON.

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Testing

A. Stub Mode (no API key required)

export TS_STUB=1
curl -sS "http://localhost:4570/api/thread-summarizer/v2/1" | jq

B. Real Mode (requires OpenAI API key)

export OPENAI_API_KEY="your-api-key"
unset TS_STUB
curl -sS "http://localhost:4570/api/thread-summarizer/v2/1" | jq

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Notes

• Users must provide their own OPENAI_API_KEY to generate real summaries.
• Without the key, the plugin runs safely in stub mode for testing.
• Caching and cooldowns ensure consistent performance and prevent repeated API usage.

[skkuwari-alt]

(I was committing to the class repo by accident, and I closed a PR there)