feat(project): 담당자는 아이디만 표기 + 구글 머티리얼 아이콘

담당자 표시를 이메일 아이디(@ 앞)로 통일. 아바타를 letter 원형에서
구글 Material Symbols account_circle 아이콘으로 교체(멤버 목록·보드 카드·
모달 선택지·리스트 뷰).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/modules/project/templates/project/project.html

@@ -1,7 +1,9 @@
 {% extends "erp_base.html" %}
 
 {% block head_extra %}
-<link rel="stylesheet" href="/static/project.css?v=20260625b" />
+<link rel="stylesheet" href="/static/project.css?v=20260625c" />
+<!-- 구글 머티리얼 심볼(담당자 아이콘 등) -->
+<link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@24,400,0,0" />
 <!-- 달력은 휴가 모듈과 동일한 서버 렌더 그리드(project.css). 타임라인만 vis(CDN, 추후 self-host) -->
 <link href="https://cdn.jsdelivr.net/npm/vis-timeline@7.7.3/styles/vis-timeline-graph2d.min.css" rel="stylesheet" />
 {% endblock %}
@@ -49,8 +51,8 @@
         <ul class="pj-member-list" id="pj-member-list">
           {% for m in members %}
           <li>
-            <span class="pj-avatar">{{ (m.user_name or m.user_email)[0] | upper }}</span>
-            <span class="pj-member-name">{{ m.user_name or m.user_email }}</span>
+            <span class="material-symbols-outlined pj-gicon">account_circle</span>
+            <span class="pj-member-name">{{ m.user_email.split('@')[0] }}</span>
             {% if m.role == 'manager' %}<span class="pj-chip pj-chip-sm">관리</span>{% endif %}
             {% if is_admin %}
             <button type="button" class="pj-icon-btn pj-del-member" data-email="{{ m.user_email }}" title="제외">×</button>
@@ -154,8 +156,8 @@
         <select id="pj-t-assignee">
           <option value="">(미지정)</option>
           {% for m in members %}
-          <option value="{{ m.user_email }}" data-name="{{ m.user_name or m.user_email }}">
-            {{ m.user_name or m.user_email }}
+          <option value="{{ m.user_email }}" data-name="{{ m.user_email.split('@')[0] }}">
+            {{ m.user_email.split('@')[0] }}
           </option>
           {% endfor %}
         </select>
@@ -200,5 +202,5 @@
 </script>
 
 <script src="https://cdn.jsdelivr.net/npm/vis-timeline@7.7.3/standalone/umd/vis-timeline-graph2d.min.js"></script>
-<script src="/static/project.js?v=20260625b" defer></script>
+<script src="/static/project.js?v=20260625c" defer></script>
 {% endblock %}