GURPS models quite a few things very well, but an AI that doesn't live in a traditional 'body' isn't one of them. In GURPS, your body and your mind are inextricably linked (at least at character creation), and your point value is based on a combination of what your mind and body let you do. Because of this, GURPS is very poor at modeling 'infomorphs' that are AI minds that control various electronic devices. There have been several attempts to make this work, but they all work orthogonally to the normal build patterns of GURPS.
That said, here are some tips and options that I think will solve your problem.
Probably don't give it No Manipulators.
No Manipulators means that you can't affect your environment physically with any kind of precision. If you have access to an engineering bay that has precision tools, or if you can command a robot to pick stuff up for you, you don't have No Manipulators. Only use this disadvantage when you have no way to physically effect your environment more precisely than, say, pushing something around with your head.
Also, if you do give it No Manipulators, it probably has a Mitigator. Since it has access to manipulators outside of itself, but it can presumably be removed from those manipulators, you can model them the same way that you model a sight-impaired person's glasses, or a person with No Legs that has prosthetic limbs.
Consider not modeling the 'AI' part of the character at all.
One thing that many GMs run into when doing super weird things in GURPS is that the modeling system has limits, and doesn't give you many tools for breaking out of those limits. If what you're going for is a character with the exact same benefits and drawbacks as the AI in SS 13, it might be easier to just list out those abilities and limitations, and use that as the 'character sheet' for the AI. At one remove from this, you could take that list of benefits and drawbacks and try and come up with a point value for it, and use that list as a racial template.
Use the Cybershell template from Transhuman Space.
There's a template in Transhuman Space - Changing Times called the Microframe/Mainframe/Macroframe template, which models an AI that lives in a non-moving computer. This template is as follows:
Attribute Modifiers: ST-10 [-100]; HT+2 .
Modifiers: HP+8 ; SM -3.
Advantages: Damage Resistance 5 (Can’t
Wear Armor, -40%) ; Doesn’t Breathe ; Machine ;
Telecommunication (Cable Jack; Sensie, +80%) ; Telecommunication
(Infrared Communication) ; Telecommunication (Radio; Sensie, +80%)
. Perks: Accessory (Computer) .
Disadvantages: Cybershell Body
[-15]; Increased Consumption 4 (1/2 hour endurance if detached from
power) [-40]; No Legs (Sessile) [-50]; No Manipulators [-50]; No Sense
of Smell/Taste [-5]; Restricted Diet (Very Common, electrical power
I'd suggest modifying the No Manipulators to more correctly model the actual manipulators available to your AI. This is probably a solid enough template to give you a good start.