feat(feedback): 新增用户反馈提交、分页列表与语音描述

支持 Bug/需求提交、截图与聊天同款语音输入，全站反馈分页浏览与详情页，并从聊天与空间页提供入口。

Co-authored-by: Cursor <cursoragent@cursor.com>

schema.sql

@@ -1072,3 +1072,20 @@ CREATE TABLE IF NOT EXISTS h5_user_memory_items (
   CONSTRAINT fk_h5_user_memory_evidence FOREIGN KEY (evidence_message_id) REFERENCES h5_conversation_messages(id) ON DELETE SET NULL,
   CONSTRAINT fk_h5_user_memory_session FOREIGN KEY (source_session_id) REFERENCES h5_user_sessions(agent_session_id) ON DELETE SET NULL
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+CREATE TABLE IF NOT EXISTS h5_user_feedback (
+  id CHAR(36) PRIMARY KEY,
+  user_id CHAR(36) NOT NULL,
+  type ENUM('bug', 'feature', 'other') NOT NULL,
+  title VARCHAR(120) NOT NULL,
+  description TEXT NOT NULL,
+  contact VARCHAR(120) NULL,
+  status ENUM('pending', 'reviewing', 'resolved', 'closed') NOT NULL DEFAULT 'pending',
+  images_json JSON NULL,
+  context_json JSON NULL,
+  created_at BIGINT NOT NULL,
+  updated_at BIGINT NOT NULL,
+  KEY idx_h5_user_feedback_user_created (user_id, created_at),
+  KEY idx_h5_user_feedback_status_created (status, created_at),
+  CONSTRAINT fk_h5_user_feedback_user FOREIGN KEY (user_id) REFERENCES h5_users(id) ON DELETE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;