fix: remove progression save on shared entry

Shared entry does not link to any user and therefore should not display
any saved progression. Curiously, the progression of a user (the one that shared ?)
was still integrated in the page. This does not make sens regarding the sharing
feature itself. It is also a leak of user personal information onto a public page.

I simply removed the data from the template when the user object is not present.
I tested the change on "regular" entry page, ensuring the save progression feature
still works, and on shared page checking if any error happened in the JavaScript console.
Everything seems in order.

internal/template/templates/views/entry.html

@@ -171,12 +171,12 @@
     {{ if hasPrefix .MimeType "audio/" }}
     <div class="enclosure-audio" >
         <audio controls preload="metadata"
-            data-last-position="{{ .MediaProgression }}"
+            {{ if $.user }}data-last-position="{{ .MediaProgression }}"{{ end }}
             {{ if $.user.MediaPlaybackRate }}data-playback-rate="{{ $.user.MediaPlaybackRate }}"{{ end }}
             {{ if $.user.MarkReadOnMediaPlayerCompletion }}
                data-mark-read-on-completion="0.9"
             {{ end }}
-            data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"
+            {{ if $.user }}data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"{{ end }}
             data-enclosure-id="{{.ID}}"
             >
             {{ if (and $.user (mustBeProxyfied "audio")) }}
@@ -190,12 +190,12 @@
         {{ else if hasPrefix .MimeType "video/" }}
         <div class="enclosure-video">
             <video controls preload="metadata"
-                data-last-position="{{ .MediaProgression }}"
+                {{ if $.user }}data-last-position="{{ .MediaProgression }}"{{ end }}
                 {{ if $.user.MediaPlaybackRate }}data-playback-rate="{{ $.user.MediaPlaybackRate }}"{{ end }}
                 {{ if $.user.MarkReadOnMediaPlayerCompletion }}
                     data-mark-read-on-completion="0.9"
                 {{ end }}
-                data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"
+                {{ if $.user }}data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"{{ end }}
                 data-enclosure-id="{{.ID}}"
                 >
                 {{ if (and $.user (mustBeProxyfied "video")) }}
@@ -225,12 +225,12 @@
         {{ if hasPrefix .MimeType "audio/" }}
         <div class="enclosure-audio">
             <audio controls preload="metadata"
-                data-last-position="{{ .MediaProgression }}"
+                {{ if $.user }}data-last-position="{{ .MediaProgression }}"{{ end }}
                 {{ if $.user.MediaPlaybackRate }}data-playback-rate="{{ $.user.MediaPlaybackRate }}"{{ end }}
                 {{ if $.user.MarkReadOnMediaPlayerCompletion }}
                     data-mark-read-on-completion="0.9"
                 {{ end }}
-                data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"
+                {{ if $.user }}data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"{{ end }}
                 data-enclosure-id="{{.ID}}"
                 >
                 {{ if (and $.user (mustBeProxyfied "audio")) }}
@@ -244,12 +244,12 @@
         {{ else if hasPrefix .MimeType "video/" }}
         <div class="enclosure-video">
             <video controls preload="metadata"
-                data-last-position="{{ .MediaProgression }}"
+                {{ if $.user }}data-last-position="{{ .MediaProgression }}"{{ end }}
                 {{ if $.user.MediaPlaybackRate }}data-playback-rate="{{ $.user.MediaPlaybackRate }}"{{ end }}
                 {{ if $.user.MarkReadOnMediaPlayerCompletion }}
                     data-mark-read-on-completion="0.9"
                 {{ end }}
-                data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"
+                {{ if $.user }}data-save-url="{{ route "saveEnclosureProgression" "enclosureID" .ID }}"{{ end }}
                 data-enclosure-id="{{.ID}}"
                 >
                 {{ if (and $.user (mustBeProxyfied "video")) }}