Refactor Stage 1 API and implement stage 2 API

[TakalaWang]

Support following endpoint API:

---

Create conversation

Method: POST
Endpoint: /api/session/[id]/group/[group_number]/conversations/+server.ts
RequestBody: {
task: string
subtasks: string[]
resources: string[]
}

---

Chat with LLM on conversation

Method: POST
Endpoint: /api/session/[id]/group/[group_number]/conversations/[conv_id]/chat/server.ts
RequestBody: {
content: string
audio: string // audio file id
}

---

Summary chat history for student in stage 1

Method: GET
Endpoint: /api/session/[id]/group/[group_number]/conversations/[conv_id]/summary/server.ts

---

Add one new discussion in group

Method: POST
Endpoint: /api/session/[id]/group/[group_number]/discussions/add/+server.ts
RequestBody: {
content: string
speaker: string // speaker name not id
}

---

Summary the group discussions

Method: GET
Endpoint: /api/session/[id]/group/[group_number]/discussions/summary/+server.ts

---

Update the group discussions summary

Method: PUT
Endpoint: /api/session/[id]/group/[group_number]/discussions/summary/+server.ts

[Copilot]

Copilot reviewed 6 out of 15 changed files in this pull request and generated 4 comments.

Files not reviewed (9)

• .env.example: Language not supported
• package.json: Language not supported
• src/routes/api/stt/+server.ts: Evaluated as low risk
• src/lib/schema/conversation.ts: Evaluated as low risk
• src/lib/server/prompt.ts: Evaluated as low risk
• src/lib/server/llm.ts: Evaluated as low risk
• scripts/pdf2text.ts: Evaluated as low risk
• src/routes/api/session/[id]/group/[group_number]/conversations/[conv_id]/summary/+server.ts: Evaluated as low risk
• src/lib/server/pdf.ts: Evaluated as low risk

Comments suppressed due to low confidence (1)

src/routes/api/session/[id]/group/[group_number]/add_discussion/+server.ts:29

• Ensure that 'discussions' is an array before spreading it to avoid potential runtime errors.

if (!data || !data.discussions) {