Fix implicit multiplication: handle cases like (25)2 → 25*2

[adithya-naik]

Fixes #2451

Description of the changes:

• Added handling for implicit multiplication after parentheses, e.g., (25)2 → (25)*2.
• Updated parser logic to insert * automatically when a number follows a closing parenthesis.
• This ensures expressions like 900+(25)2 evaluate correctly as 950.

How changes were validated:

• Full Calculator app was not built due to local environment constraints, but logic matches expected results.