gnoweb(url): remove the possibility to have $ after the query

[gfanton]

Following #2876, I believe we should eliminate the option to use $ after the query. I don't mind using $ as a second query component, but it should remain in the path to adhere to standard URI format. Including $ after the query ? may not be supported by most API tools and could lead to potential parsing errors or conflicts.
I think we should also establish a specific order to avoid confusion and to align more naturally with the actual composition of URI. Therefore, I propose the order as : -> $ -> ? -> #.
I don't believe these restrictions will significantly affect current behaviors too much. Instead, they may help prevent future incompatibility issues and parsing difficulties.

Taking previous examples:

• 🟢 https://gno.land/r/demo/foo$help&func=Bar&name=Baz
• 🟢 https://gno.land/r/demo/foo:example$tz=Europe/Paris?value=42
• 🟠 https://gno.land/r/demo/foo:example?value=42$tz=Europe/Paris <-- value should equal 42$tz=Europe/Paris

cc @jeronimoalbi @leohhhn @moul @alexiscolin wdyt ?