Rewrite ownership to use faction_id to avoid pointer crashes

[ghost]

Summary

SUMMARY: Bugfixes "Rewrite ownership to use faction_id to avoid pointer crashes"

Purpose of change

Fixes #34209
Fixes #34212

Ownership used pointers to factions, this all seemed fine before dynamic factions.
Now when a dynamic faction is deleted, then everything they ever touched now belongs to a dangling pointer.

This requires a rewrite of ownership to use ids for safety and less crashes ( hopefully )

Describe the solution

rewrite vehicle and item ownership to use faction_id , and edit the associated structure and functions to support that

Describe alternatives you've considered

Other solution was to potentially keep dead factions around forever, but that didnt seem viable.

Additional context

I am not quite happy with this solution, Ive had to rewrite a lot, and going by what ive done recently with factions, I expect lots more bugs. Im operating at the edge of what I know how to do, but the onus is on me to fix what I broke, so this is my best effort at that.
I would appreciate scrutiny on this, ive tested and it seems ok, but I cannot judge from the code alone if this is a suitable rewrite.

[mlangsdorf]

In general, you want to encapsulate all of this stuff. That means set_owner() should have a version that takes a player as an argument and does the right thing, and all of this

if( it.has_owner() ) {
    const faction_id item_fac = it.get_owner();
    if( item_fac != g->u.get_faction()->id ) {

should simply be

if( !it.owned_by_player( g->u, true ) ) {

I didn't go through line by line, but just about about time you changed a function parameter from faction * to faction_id was a time when you should have encapsulated the logic instead.

[mlangsdorf]

Getting better, but you need to encapsulate more. The only time you should dealing with faction->id() is inside the accessor functions or when you only have a faction *.

Also, consistently use Character & instead of player & now that the g->u has a get_fac() function.

[ghost]

More encapsulation, not tested yet, need to sleep, will test tomorrow.

[ghost]

Fixed vehicle owner name display.
Tested :

1. loading old save with old faction data serialized.
2. spawning dynamic NPCs and killing them and checking owner of their dropped items.
3. killing followers and checking their dropped items.
4. going to refugee center, checking their owned items and vehicles.
5. saving/loading in refugee center.

All seems fine.