fix: 归零玩法创作初始进度

server-rs/crates/spacetime-module/src/big_fish/session.rs

@@ -182,7 +182,8 @@ pub(crate) fn create_big_fish_session_tx(
             owner_user_id: input.owner_user_id.clone(),
             seed_text: input.seed_text.trim().to_string(),
             current_turn: 0,
-            progress_percent: 20,
+            // 中文注释：欢迎语和种子推断只是初始上下文，不代表创作者已经推进了共创流程。
+            progress_percent: 0,
             stage: BigFishCreationStage::CollectingAnchors,
             anchor_pack_json: serialize_anchor_pack(&anchor_pack)
                 .map_err(|error| error.to_string())?,

server-rs/crates/spacetime-module/src/puzzle.rs

@@ -473,7 +473,8 @@ fn create_puzzle_agent_session_tx(
         owner_user_id: input.owner_user_id.clone(),
         seed_text: input.seed_text.clone(),
         current_turn: 1,
-        progress_percent: 18,
+        // 中文注释：欢迎语和初始锚点推断不计入创作进度，新会话必须从 0% 开始。
+        progress_percent: 0,
         stage: PuzzleAgentStage::CollectingAnchors,
         anchor_pack_json: serialize_json(&anchor_pack),
         draft_json: None,