make shortlinks case insensitive

readme.md

@@ -33,6 +33,27 @@ a _really_ simple url shortener: less than 200 lines of Rust and one dependency
 
 a working [dockerfile](./Dockerfile) and [compose file](./compose.yaml) are provided.
 
+## a note on case insensitivity
+
+all shortlinks are case insenitive,
+due to the lack of [urlencoding/decoding](#a-note-on-urlencoded-characters).
+
+## a note on urlencoded characters
+
+this program does not decode urlencoded strings before checking if strings match.
+this is a deliberate choice to keep things as simple as possible.
+
+avoid using links that may be encoded.
+
+for links that will necessarily get encoded (still discouraged) (such as emojis),
+put the urlencoded string.
+for example, for the link <http://pls.cx/🤬> the following line is in my urls.txt:
+
+```
+/🤬 https://en.wikipedia.org/wiki/Controversies_of_Nestl%C3%A9 you may want the non-encoded version in case a client does not encode it? idk
+/%f0%9f%a4%ac https://en.wikipedia.org/wiki/Controversies_of_Nestl%C3%A9
+```
+
 ## why?
 
 all url shorteners i've come across are too complicated:
@@ -47,7 +68,7 @@ updating it.
 
 good question.
 i'm not sure, but i think i want to separate my concerns?
-you might just want to configure your reverse proxy instead.
+you might just want to configure your reverse proxy instead:
 
 #### caddy