Add version history view for timer functions

- Implement `/history/<function_id>` route in timer routes to fetch and display function versions
- Create new Mithril `DiffView` component for comparing script versions
- Add new history template for timer functions with version comparison
- Include version diff functionality using AceDiff library
- Update header and edit templates to include history URL for timer functions

templates/dashboard/timer_functions/history.html

@@ -0,0 +1,26 @@
+{% extends 'dashboard.html' %}
+
+{% block page %}
+
+{{ render_partial('dashboard/http_functions/header.html',
+user_id=user_id,
+function_id=function_id,
+active_tab='history',
+show_edit_form=True,
+show_logs=True,
+show_history=True,
+edit_url=url_for('timer.edit', function_id=function_id),
+cancel_url=url_for('timer.overview'),
+logs_url=url_for('timer.logs', function_id=function_id),
+history_url=url_for('timer.history', function_id=function_id))
+}}
+
+<div id="version-diff"></div>
+
+<script>
+    // Mount the Mithril component with versions as an attribute
+    m.mount(document.getElementById("version-diff"), {
+        view: () => m(DiffView, { versions: {{ versions| tojson }} })
+    });
+</script>
+{% endblock %}