fix(wiki): citation drawer shows real data instead of empty fallbacks

Root cause: PageCitationWithRaw record only had id/pageId/chunkId/rawId/
paragraphIdx/anchorText/confidence — missing rawTitle, chunkOrdinal,
startOffset, endOffset, snippet. Frontend displayed Source + Chunk ?
for every card.

Backend:
- Extend PageCitationWithRaw with rawTitle, chunkOrdinal, startOffset,
  endOffset, snippet fields
- Expand listWithRawByPageId SQL to LEFT JOIN mate_wiki_raw_material for
  title, JOIN mate_wiki_chunk for ordinal/offsets/content snippet (first
  200 chars via SUBSTRING)

Frontend:
- CitationDrawer: replace hardcoded Source / Chunk ? / offset with
  i18n keys
- Add 4 new i18n keys: citationUnknownSource, citationChunkN,
  citationChunkUnknown, citationOffset (zh-CN + en-US)

mateclaw-server/src/main/java/vip/mate/wiki/dto/PageCitationWithRaw.java

@@ -6,4 +6,7 @@ import java.math.BigDecimal;
  * RFC-029: Citation record joined with the chunk's raw material ID.
  */
 public record PageCitationWithRaw(Long id, Long pageId, Long chunkId, Long rawId,
-                                   Integer paragraphIdx, String anchorText, BigDecimal confidence) {}
+                                   Integer paragraphIdx, String anchorText, BigDecimal confidence,
+                                   String rawTitle, Integer chunkOrdinal,
+                                   Integer startOffset, Integer endOffset,
+                                   String snippet) {}

mateclaw-server/src/main/java/vip/mate/wiki/repository/WikiPageCitationMapper.java

@@ -15,9 +15,15 @@ import java.util.List;
 @Mapper
 public interface WikiPageCitationMapper extends BaseMapper<WikiPageCitationEntity> {
 
-    @Select("SELECT c.id, c.page_id, c.chunk_id, wc.raw_id, c.paragraph_idx, c.anchor_text, c.confidence " +
+    @Select("SELECT c.id, c.page_id, c.chunk_id, wc.raw_id, " +
+            "c.paragraph_idx, c.anchor_text, c.confidence, " +
+            "rm.title AS raw_title, " +
+            "wc.ordinal AS chunk_ordinal, " +
+            "wc.start_offset, wc.end_offset, " +
+            "SUBSTRING(wc.content, 1, 200) AS snippet " +
             "FROM mate_wiki_page_citation c " +
             "JOIN mate_wiki_chunk wc ON c.chunk_id = wc.id " +
+            "LEFT JOIN mate_wiki_raw_material rm ON wc.raw_id = rm.id " +
             "WHERE c.page_id = #{pageId} AND c.deleted = 0")
     List<PageCitationWithRaw> listWithRawByPageId(@Param("pageId") Long pageId);
 

mateclaw-ui/src/i18n/locales/en-US.ts

@@ -1284,6 +1284,10 @@ export default {
       repair: 'Repair page',
       citations: '{count} source chunks',
       noCitations: 'No source citations found',
+      citationUnknownSource: 'Unknown source',
+      citationChunkN: 'Chunk {n}',
+      citationChunkUnknown: 'Chunk unknown',
+      citationOffset: 'offset {start}–{end}',
     },
     relation: {
       shared_chunk: 'Shared chunk',

mateclaw-ui/src/i18n/locales/zh-CN.ts

@@ -1294,6 +1294,10 @@ export default {
       repair: '修复页面',
       citations: '来源 {count} 个 chunk',
       noCitations: '未找到来源引用',
+      citationUnknownSource: '未知来源',
+      citationChunkN: '第 {n} 段',
+      citationChunkUnknown: '段落未知',
+      citationOffset: '偏移 {start}–{end}',
     },
     relation: {
       shared_chunk: '共享片段',

mateclaw-ui/src/views/Wiki/components/CitationDrawer.vue

@@ -12,11 +12,11 @@
         </div>
         <div v-else class="citation-list">
           <div v-for="cit in citations" :key="cit.id" class="citation-item">
-            <div class="citation-raw-title">{{ cit.rawTitle || 'Source' }}</div>
+            <div class="citation-raw-title">{{ cit.rawTitle || t('wiki.page.citationUnknownSource') }}</div>
             <div class="citation-chunk-info">
-              Chunk {{ cit.chunkOrdinal ?? '?' }}
+              {{ cit.chunkOrdinal != null ? t('wiki.page.citationChunkN', { n: cit.chunkOrdinal }) : t('wiki.page.citationChunkUnknown') }}
               <span v-if="cit.startOffset != null" class="citation-offset">
-                (offset {{ cit.startOffset }}–{{ cit.endOffset }})
+                ({{ t('wiki.page.citationOffset', { start: cit.startOffset, end: cit.endOffset }) }})
               </span>
             </div>
             <div v-if="cit.snippet" class="citation-snippet">"{{ cit.snippet }}"</div>