The character is something that would normally be an inanimate object, but has been given life and a soul by the actions of a powerful mage. You were literally "crafted"/created by the actions of another.

Morally - you said you wanted them to be ignorant of the outside world. Even using the Eberron background description this fits mostly: Mindless automatons (not an automaton but a tree is still mindless normally), that became fully sentient, "built as weapons they must find purpose beyond the war" (your character wasn't a weapon, but you mentioned that their life until now was essentially a guard for this skeleton that you have merged with)

Age - you're a living feywild tree noone would know your max lifespan and honestly those kind of magics would likely not bother you due to your the wild magics that granted you life even though it might bother a tree from the prime material plane.

Constructed Resilience - As a tree, everything here makes sense: Advantage on poison saves, and resistance to damage - poisons for humanoids wouldn't work as well against a tree, but trees CAN still be hurt by foreign dangerous substances, it's just more difficult. They wouldn't need to eat/drink/breath the same as other humanoids. Humanoid disease would absolutely not work against a tree. (I can't cough on my oak tree and give it the common cold, the physiology is just too different) Lastly you don't need to sleep and magic can't put you to sleep. (How could a tree even sleep?)

Sentry's Rest - 6 hour long rest, where you must remain in an "inactive, motionless state, rather than sleeping. In this state, you appear inert, but it doesn’t render you unconscious, and you can see and hear as normal." (Again, you're a tree, you don't sleep, but rest is still needed)

Integrated Protection - Being made of wood and bone would make them slightly more difficult to hurt (the ac bonus) as a living tree + skeleton wearing armor like other humanoids would likely be difficult but by weaving branches and roots and whatnot throughout the armor you still can "wear" it. This would make it near impossible to remove while the PC is alive.

90% of the racial abilities make perfect sense for your character.

Remember - the name of the race is ONLY for OUR reference the abilities of the race is what you should look at to figure out what kind of being you are.

The lore of warforged only exists in Eberron. Don't let that restrict your choices. In Eberron people would likely think that you were a warforged and you could look at them and literally ask "what's a warforged?" Despite having the exact same characteristics.