fix(channel): fix shorts/streams pagination using continuation tokens

- Add continuation_token_cache to store ctokens between page requests
- Use cached ctoken for page 2+ instead of generating fresh tokens
- Switch shorts/streams to Next/Previous buttons (no page numbers)
- Show "N+ videos" indicator when more pages are available
- Fix UnboundLocalError when page_call was undefined for shorts/streams

The issue was that YouTube's InnerTube API requires continuation tokens
for pagination on shorts/streams tabs, but the code was generating a new
ctoken each time, always returning the same 30 videos.

1 files changed, 10 insertions, 2 deletions

diff --git a/youtube/templates/channel.html b/youtube/templates/channel.html
index 2c0a1a2..274b727 100644
--- a/youtube/templates/channel.html
+++ b/youtube/templates/channel.html
@@ -82,7 +82,11 @@
         <div id="links-metadata">
                 {% if current_tab in ('videos', 'shorts', 'streams') %}
                     {% set sorts = [('3', 'newest'), ('4', 'newest - no shorts')] %}
-                    <div id="number-of-results">{{ number_of_videos }} videos</div>
+                    {% if current_tab in ('shorts', 'streams') and not is_last_page %}
+                        <div id="number-of-results">{{ number_of_videos }}+ videos</div>
+                    {% else %}
+                        <div id="number-of-results">{{ number_of_videos }} videos</div>
+                    {% endif %}
                 {% elif current_tab == 'playlists' %}
                     {% set sorts = [('3', 'newest'), ('4', 'last video added')] %}
                     {% if items %}
@@ -117,7 +121,11 @@
         <hr/>
 
         <footer class="pagination-container">
-            {% if current_tab in ('videos', 'shorts', 'streams') %}
+            {% if current_tab in ('shorts', 'streams') %}
+                <nav class="next-previous-button-row">
+                    {{ common_elements.next_previous_buttons(is_last_page, channel_url + '/' + current_tab, parameters_dictionary) }}
+                </nav>
+            {% elif current_tab == 'videos' %}
                 <nav class="pagination-list">
                     {{ common_elements.page_buttons(number_of_pages, channel_url + '/' + current_tab, parameters_dictionary, include_ends=(current_sort.__str__() in '34')) }}
                 </nav>