docs: fix Pinecone index name mismatch between README, NewsModel.py, and Database.py

[Shrishagk]

Summary

Fixes #237 — the README instructs users to create a Pinecone index named news-index, but the actual code never reads that name. The read path (NewsModel.py) hardcodes a different literal (cybernews-hybrid-test-2) than the write path (db_update/Update.py, which already reads PINECONE_INDEX_NAME from .env), so following the README exactly still results in a broken setup — the read and write paths point at two different indexes with no single value a user can set to make them agree.

This PR makes PINECONE_INDEX_NAME the single source of truth for both paths, removes an unused hardcoded name, and updates the README to match.

Changes

models/NewsModel.py (line 8)
Replaced the hardcoded self.index_name = "cybernews-hybrid-test-2" with the same .env-driven lookup already used in db_update/Update.py:

# Before
self.index_name = "cybernews-hybrid-test-2"

# After
self.index_name = str.lower(dotenv_values(".env").get("PINECONE_INDEX_NAME"))

Added from dotenv import dotenv_values to support this.

config/Database.py (line 11)
Removed the unused index_name = "cybernews-index" variable. It was never imported anywhere else in the codebase (only client is imported from this module), so this is dead-code cleanup with no behavioral impact — but it removes a third, misleading candidate name from the source for anyone trying to figure out the "correct" index name.

db_update/Update.py
No change — this file was already correct. It's the reference implementation for the PINECONE_INDEX_NAME pattern now applied to NewsModel.py.

README.md (line 32)

# Before
Login to Pinecone and create a new index with the name `news-index`. Then, add the Pinecone API key in the `.env` file.

# After
Login to Pinecone and create a new index with a name of your choice. Then, add the Pinecone API key and your chosen index name to the `.env` file as `PINECONE_API_KEY` and `PINECONE_INDEX_NAME` respectively (see `.env.example`).

Why

• Before: creating news-index per the README and setting only PINECONE_API_KEY causes db_update/Update.py to crash (PINECONE_INDEX_NAME is None, and str.lower(None) raises TypeError). Setting PINECONE_INDEX_NAME=news-index to work around that lets db_update/Update.py populate news-index successfully — but NewsModel.py still queries cybernews-hybrid-test-2, which doesn't exist, so every /news and /news_keywords request returns empty results.
• After: one env var (PINECONE_INDEX_NAME) controls both the write path and the read path, and the README no longer hardcodes a name the code doesn't use.

Scope

This applies to the root application (app.py, config/, models/, db_update/) — the pre-migration, Pinecone-based path the README's Setup section documents. api-service/ (used by docker-compose.yml) has already moved off Pinecone onto Postgres + pgvector and is unaffected by this change.

Testing

• Set PINECONE_INDEX_NAME in .env to a name of your choice
• Run db_update/Update.py — confirm it creates/populates that index without error
• Run the app (flask --app app.py run) and hit /mistralai/news — confirm it now returns data from the same index db_update/Update.py populated

Related

Fixes #237