Feature Request: Add Watchlist Feature to Investra

[muskan171105]

Implement a watchlist feature that allows users to:

• Add and remove stocks from their watchlist.
• View their current watchlist on a dedicated component.
• Store watchlist data in the MongoDB database, linked to user accounts.
• Display stock symbols with remove options.

Please assign me this issue under GSSoC and Hacktoberfest

[SanchitGeez]

start working ...i'll assign the labels in a couple of days