Steering tyres are out of balance, this might be cured when the knackered tyre is replaced it might not, it might help if the tyre were to gain a puncture 
and when flat you drove it a few hundred yards slowly to finish it off.
You might try lubing the window winder mechanism, and squirt some silicone lube into the window’s guide channels, should sort the window issue between them.
The screen washer thing, you might be able to sort yourself, but if the gaffer supplies washer fluid just keep throwing it in, when he’s gone through £100 worth of washer fluid that’s done nothing other than leak out on the floor he’ll get the message.
Fuel sender, just note the mileage when you fill up and make a note of when you’ll need to top up.
Use hazards for reverse lights for the time being, presumably you’ve checked the bulbs and squirted some contact cleaner into the suzy connectors.
We’ve all worked for people like this in the past, and there are far worse out there, drivers often sort little faults and minor lubing out themselves whilst waiting around.
Before you go jumping ship look at the job on its merits, and think laterally how you could make these faults pay you personally, if you’re hourly paid and a 3 hour run takes you 5 hours because you have to stop and clean the screen so be it, when he asks why tell him why.
If the job pays rather well, then it might be worth sorting some of these issues out yourself, ie if you’re earning £50 or £150 a week more than driving some corporate fleet motor that’s perfectly maintained, but you’re under the watchful eye of a driver facing camera and some snotty nose brat is clocking you on a tracker itching to report you for some transgression.
Course if the job is crap anyway then it won’t hurt to keep an eye open for something better.
You’re new to the game, the very last thing i would do is report the place to DVSA as suggested, it won’t take a genius to work out who grassed and whilst it might not have immediate repercussions physically for you, your name will stink for a very long time in the district as these things get talked about (drivers are the worlds worse gossips) and you might find getting another job hard.
Lastly, this app thing is probably being deleted daily, a defect book is a permanent record of defects (photocopy and keep one for your records), or you could send the gaffer an email detailing the serious faults which will be a similar permanent record and a valuable bit of evidence to your benefit should anything happen.
