feat: paginate and search brand questions across selects

Make GET /api/tenant/brands/:id/questions return a paginated
QuestionListResponse (items/total/page/page_size) with optional `q`
full-text filter, validated page/page_size query params, and per-params
cache keys. Add a usePaginatedBrandQuestions composable backing the
imitation, template-wizard, and tracking question selects with
search-as-you-type and infinite scroll, plus ensure-loaded-by-id so a
deep-linked or pre-selected question is fetched even when off the first
page. Brands view now drives its questions table via server pagination.

Also redesign the Tracking hot-questions and cited-articles lists
(mention-rate badges/bars, metric groups, refreshed styling) and fall
back to citation-fact article_id/title when no high-confidence URL alias
matches, so cited articles surface even without an alias row.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

server/internal/shared/swagger/descriptions.go

@@ -333,7 +333,7 @@ var routeDocs = map[string]routeDoc{
 	"PUT /api/tenant/brands/:id/keywords/:kid":    {"更新关键词", "修改关键词文本/分组。"},
 	"DELETE /api/tenant/brands/:id/keywords/:kid": {"删除关键词", "删除某条关键词。"},
 
-	"GET /api/tenant/brands/:id/questions":                      {"搜索词列表", "返回品牌下的监控搜索词，可按 keyword_id 过滤。"},
+	"GET /api/tenant/brands/:id/questions":                      {"搜索词列表", "分页返回品牌下的监控搜索词，可按 keyword_id 过滤，支持 q 搜索。"},
 	"POST /api/tenant/brands/:id/questions":                     {"新增搜索词", "为品牌添加一条 GEO 监控搜索词。"},
 	"POST /api/tenant/brands/:id/questions/combination-preview": {"拓词工具预览", "按地域词、前缀词、精准词、行业词、后缀词组合生成搜索词候选，仅预览不入库。"},
 	"POST /api/tenant/brands/:id/questions/combination-fill":    {"拓词工具 AI 填词", "根据用户 IP 本地识别地域，并结合品牌信息补全拓词工具的五列词组。"},