I have read the sentence: 你还记得我吗？ But I can’t understand the meaning of 得, here. I don’t think it belongs to the rules explained here
Very briefly, you should be aware that one additional meaning of 得 (de2) is to obtain.
Examples of this usage include 得到 and 获得.
In this particular instance, I think of 记得 as being 记 + 得, where the 记 means memory, 得 means to obtain, and put together we have: to obtain a memory. Thus, 记得 means to remember.
In the example sentence you give,
记得 as a whole:
First I take back my comment saying 记得 is one word, but I keep the part that it should be understood as a whole.
记得 is a 离合词 (cleft word, a.k.a. separable word). Most, if not all, cleft words do appear in dictionary as a word, however in grammar, whether they're words or phrases is still being debated by the professionals. No wonder there's a lot of confusion across the answers and comments.
There are different types of cleft words. 记得 falls into the type 'verb+result', where
Words with the same structure include: 看见, 听懂, 叫醒, etc.
Words with the same structure AND the 'result' word is also '得' include: 认得, 晓得, etc.
As a result, 得 in 记得 has the same meaning as in 得到, which is 'to obtain', although the syntactic roles are very different (in 得到, '得' is the action verb and '到' is the resultative complement). You're right that this usage is not listed in the link you have in the question.
Since we've touched the subject of cleft words, let's explore more about them:
As a 'verb+result' cleft word, 记 and 得 can be infix-ed by a resultative particle to affirm/negate the result, or construct an interrogative pattern. Which means,
'记得得' is grammatical, but seldom used due to the pronunciation difficulty caused by the repetition of '得'.
Besides these patterns specific to cleft words, they can also apply the common verb pattern of 'word+不/没+word' for interrogative pattern. The meaning is exactly the same as #3 above.
记不得 vs. 不记得:
There is a common confusion between them and some people misuse them as if 记不得 means 'I used to remember but now forgot'; 不记得 means 'I tried to remember but never succeeded'.
Generally, 'verb+不/没+result' means 'cannot do' and '不/没+verb+result' means 'do not do', for example,
However when it comes to 记得, although logically 记不得 means 'I don't have the ability to remember' and 不记得 means 'It's not in my memory', in practice they are both used for the same meaning of 'I don't remember' and are interchangeable. 记不得 is never used to describe someone's poor memorizing ability and you need some other expression for that.
Having said that, there is a difference in the usage, which is in geographical popularity. People from Northern China are more accustomed to say 不记得, while people from Southern China are okay to say both.
得 as in 记得住:
记住 is also a 'verb+result' cleft word. 记得住 is 记住 infix-ed with affirmative particle 得 (pattern 'verb+得+result' for affirmation). Similar examples include 看得见, 跑得快, etc. 记 and 得 happen to be neighbors in this phrase, but it has nothing to do with the cleft word 记得.
I check the link OP used. It is very close, or actually answered the question.
It is in the B1 category. The site contains many specific long examples, but none with the exact format OP is looking for.
It is very difficult to "explain" or give a translation to
I hope this helps and not being too confusing.
I would translate 得 as "able" (for emphasis). So, 你还记得我吗？would mean, "Are you still (able) to remember me?