Use Ructe (#327)

All the template are now compiled at compile-time with the `ructe` crate.

I preferred to use it instead of askama because it allows more complex Rust expressions, where askama only supports a small subset of expressions and doesn't allow them everywhere (for instance, `{{ macro!() | filter }}` would result in a parsing error).

The diff is quite huge, but there is normally no changes in functionality.

Fixes #161 and unblocks #110 and #273

templates/partials/comment.rs.html

@@ -0,0 +1,27 @@
+@use template_utils::*;
+@use plume_models::comments::Comment;
+@use plume_models::users::User;
+
+@(ctx: BaseContext, comm: &Comment, author: User)
+
+<div class="comment" id="comment-@comm.id">
+    <a class="author" href="/@@/@author.get_fqn(ctx.0)/">
+        @avatar(ctx.0, &author, Size::Small, true, ctx.1)
+        <span class="display-name">@author.name(ctx.0)</span>
+        <small>@author.get_fqn(ctx.0)</small>
+    </a>
+    <div class="text">
+        @if comm.sensitive {
+            <details>
+                <summary>@comm.spoiler_text</summary>
+        }
+        @Html(&comm.content)
+        @if comm.sensitive {
+            </details>
+        }
+    </div>
+    <a class="button icon icon-message-circle" href="?responding_to=@comm.id">@i18n!(ctx.1, "Respond")</a>
+    @for res in comm.get_responses(ctx.0) {
+        @:comment(ctx, &res, res.get_author(ctx.0))
+    }
+</div>