bug: RAG - Stuck in generating response and other related glitchs

[Van-QA]

Describe the bug A clear and concise description of what the bug is.

1. Pipeline issue - Nightly build are not able to run RAG:

VDB we are using in this MVP - HNSWLib is not universally built to distribute.

2. Unable to regenerate the RAG response using the reload button:

Stuck in generating w/o any details added to App.log, users stuck in this state indefinitely, can not regenerate the RAG reponse.

3. With Retrieval ON - Glitch when switching to another page and back, the selected model does not preserved.

The model selector also glitched and showed choose model to start when there is already an active model.

4. Moving RAG to experimental feature

5. Opening the uploaded file:

• The label is "Show in Finder" in Windows
• The file is opened directly instead of just opening the contained folder

================================ Environment details

• Operating System: MacOS
• Jan Version: latest nightly build
• Processor: Apple M2 Pro
• RAM: 16GB
• Any additional relevant hardware specifics: [e.g., Graphics card, SSD/HDD]

Logs If the cause of the error is not clear, kindly provide your usage logs:

• tail -n 50 ~/jan/logs/app.log if you are using the UI
• tail -n 50 ~/jan/logs/server.log if you are using the local api server Making sure to redact any private information.

Additional context Add any other context or information that could be helpful in diagnosing the problem.

[hantran-co]

related ticket: https://github.com/janhq/jan/issues/1861

[louis-jan]

Issue 2: Since Nitro's embedding does not implemented queue mechanism, can reproduce easily when spamming requests. Will keep track in a separated issue