Rewrite and restyle reaction selector and enable no-sizzle eslint rule (#30453) (#30473)

Backport #30453 by @silverwind

Enable `no-sizzle` lint rule, there was only one use in
`initCompReactionSelector` which I have rewritten as follows:

- Remove all jQuery except the necessary fomantic dropdown init
- Remove the recursion, instead bind event listeners to common parent
container nodes

Did various tests, works with our without attachments, in diff view and
in diff comments inside comment list.

Additionally the style of reactions now matches between code comments
and issue comments:

<img width="275" alt="Screenshot 2024-04-13 at 14 58 10"
src="https://github.com/go-gitea/gitea/assets/115237/9d08f188-8661-4dd9-bff4-cad6d6d09cab">

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

web_src/css/repo/reactions.css

@@ -0,0 +1,70 @@
+.bottom-reactions {
+  display: flex;
+  gap: 6px;
+  margin: 0 1em 1em;
+}
+
+.timeline-item .conversation-holder .bottom-reactions {
+  margin: 1em 0 0 36px;
+  padding-bottom: 8px;
+}
+
+.bottom-reactions .ui.label {
+  padding: 5px 8px;
+  font-weight: var(--font-weight-normal);
+}
+
+.bottom-reactions .ui.label.primary {
+  background-color: var(--color-reaction-active-bg) !important;
+}
+
+.bottom-reactions .ui.label:hover {
+  background-color: var(--color-reaction-hover-bg) !important;
+}
+
+.bottom-reactions .ui.label.disabled {
+  cursor: default;
+  opacity: 1;
+}
+
+.bottom-reactions .ui.label .reaction {
+  font-size: 16px;
+  display: flex;
+}
+
+.bottom-reactions .ui.label .reaction img {
+  height: 16px;
+  aspect-ratio: 1;
+}
+
+.bottom-reactions .reaction-count {
+  margin-left: 4px;
+}
+
+.ui.dropdown.select-reaction .menu {
+  min-width: 170px; /* item-outer-width * 4 */
+}
+
+.ui.dropdown.select-reaction .menu > .item {
+  float: left;
+  margin: 4px;
+  font-size: 20px;
+  width: 34px;
+  height: 34px;
+  border-radius: var(--border-radius);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.bottom-reactions .select-reaction {
+  padding: 0 10px;
+}
+
+.bottom-reactions .select-reaction:not(.active) {
+  visibility: hidden;
+}
+
+.bottom-reactions:hover .select-reaction {
+  visibility: visible;
+}