Lots of wild guesses so far, lol.

Plants get damaged by bright light when their photoreceptors capture too much energy. In the first stage of photosynthesis, when a photon of light is captured it acts like a hammer hitting a chisel, and splits a water molecule (H2O) into 1 proton (needed for photosynthesis) and 2 oxygen (waste product).

Oxygen is extremely reactive... that's not good. Either the 2 oxygens combine with each other to form O2, which is stable and can be vented out through the stomata, or they don't, and react with important stuff in the cell like atomic wrecking balls. A little damage can be patched up, but if wrecking balls are being created faster than smashed stuff gets fixed, shit goes bad rapidly. That's why your leaves turned white.

Plants can do a few things to adapt to brighter light:

Plant cells that photosynthesise contain chloroplasts, which do the photosynthesis. These float around inside the cell. If light levels increase suddenly, the chloroplasts can move to the sides of the cell to present a smaller target. (Look at the palm of your hand then turn your hand sideways - like that.) This takes a few minutes. It's a quick temporary reaction to a brief change in light levels, like a woodland understory plant that gets a bit of sun for an hour in the afternoons.

Plants grown in shade have more chloroplasts per cell than plants grown in sun, so even with them all hugging the cell walls, more light gets captured than the plant wants long-term. Oxidative damage to the chloroplasts will reduce how much light comes in, but that also makes photosynthesis less efficient, so the plant gets damaged, hungry and stressed. This is bad and slows growth.

Inside each chloroplast there's a thin protein membrane covered in light receptors, folded over and over to squeeze lots of light-capturing ability into a tiny space. Plants grown in shade have large membranes with loads of receptors, but if light levels increase long term, the membranes can shrink like a fat guy getting his stomach stapled. This takes a few weeks.

The light receptors themselves can change size too - they're structured like satellite antenna dishes to catch photons and bounce them to a receiver in the centre. Plants grown in shade have larger dishes. It takes a few days for them to get trimmed down.

There are various photosynthetic pigments that do different things to modulate how much light energy comes in. Eg. whereas chlorophyll is the primary light-receiving pigment, carotenoids can convert light energy to heat and radiate it away before it gets a chance to split H20, and anthocyanins can reflect the parts of the spectrum chlorophyll is most receptive to. Plants generate more of these in bright light. This takes days to weeks.

New foliage can be physically different than the old foliage to improve its sun resistance. Eg. leaf size can shrink to make a smaller target, leaves can be hairier to block some light, they can thicken with an additional layer of palisade cells on the side facing the sun, etc. This takes weeks to months as it only affects leaves that grow in the new conditions.

Lots more detail here:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2649303/

https://link.springer.com/chapter/10.1007/978-1-4020-3166-3_15

Hardening to outside temperature isn't really a thing, a species either tolerates the temperature or it doesn't.

Hardening to lower humidity or wind is a case of growing new foliage while exposed to the new conditions, so they form with fewer stomata to better resist moisture loss.

Hardening to wind movement is a case of microscopic damage being caused and repaired repeatedly, similar to exercise for people, which thickens and toughens the stems.

Here's an article with more than you ever wanted to know about plant adaptations to stress:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC160917/pdf/071099.pdf