urlpaths: seemingly full functionality

various subpath combos seem to work, and trailing slashes from them are
trimmed (including for the empty admin path "/", which is now "" by
default).

config/config-base.yaml

@@ -194,12 +194,10 @@ sections:
     value: Your account has been created. Click below to continue to Jellyfin.
     description: Displayed when a user creates an account. Use the "post-signup card"
       in the Message editor for more control.
-  - setting: url_base
-    name: Reverse Proxy subfolder
-    requires_restart: true
-    type: text
-    description: URL base for when running jfa-go with a reverse proxy in a subfolder.
-      include preceding /, e.g "/accounts".
+  - setting: subfolder_note
+    name: "Reverse proxy-ing to a subfolder?"
+    type: note
+    description: "Put the folder (e.g. /accounts) in \"Reverse Proxy subfolder\", and the full URL including it (e.g. https://jellyf.in/accounts) in \"External jfa-go URL\"."
   - setting: jfa_url
     name: External jfa-go URL
     required: true
@@ -209,6 +207,12 @@ sections:
     description: The URL at which the jfa-go root (admin page) is accessible, including
       the subfolder if you use one. This is necessary because using a reverse proxy
       means the program has no way of knowing the URL itself.
+  - setting: url_base
+    name: Reverse Proxy subfolder
+    requires_restart: true
+    type: text
+    description: URL base for when running jfa-go with a reverse proxy in a subfolder.
+      include preceding /, e.g "/accounts".
   - setting: redirect_url
     name: Form success redirect URL
     type: text
@@ -232,10 +236,14 @@ sections:
     - ["opaque", "Opaque"]
     value: clear
     description: Appearance of the Admin login screen.
+  - setting: urlpaths_note
+    name: "URL Paths:"
+    type: note
+    description: "Want \"My Account\" at \"/\" or the admin page at \"/admin\"? Enable advanced settings and check the \"URL Paths\" section."
 - section: url_paths
   meta:
     name: URL Paths
-    description: Settings for changing where different pages are accessed.
+    description: Settings for changing where different pages are accessed. If you change & forget these, they're printed in the logs on startup. Paths should have a slash at the beginning but not at the end.
     advanced: true
   settings:
   - setting: admin
@@ -243,7 +251,7 @@ sections:
     type: text
     required: true
     requires_restart: true
-    value: "/"
+    value: ""
     description: URL subpath the admin page should be at.
   - setting: user_page
     name: "\"My Account\" subpath"