Is it obligatory to enter into a state of Ihram for Umrah from the Miqat, or is it permissible to enter into Ihram from Jeddah, given that I have resided there for 4 days?

If you arrive in Jeddah for work, and you intend to perform 'Umrah if possible, you are not obligated to enter into theramiht for 'Umrah. However, if you intend to perform 'Umrah and go to work during this trip, then you must enter into ihram from the miqat.

If you wish to enter into ihram for 'Umrah while you are in Jeddah, your ihram will be from your place of residence, based on the general statement of the Prophet, peace and blessings be upon him: "And whoever is within that [meaning, within the miqats], then from where he originates [his journey]."