chore(planner): delete injectStructuralSkills

Remove the v10 rule-based structural skill injection method. This was the
legacy path that injected golden-opening rules, paywall hints, mood
pressure, and hook resolve guidance into mustKeep/styleEmphasis arrays.

These concerns are now handled by the methodology-aware LLM system prompt
(principles 1-11 + opening toolbox). The LLM planner reads the same
materials and applies methodology principles directly in brief generation.

packages/core/src/agents/planner.ts

@@ -925,77 +925,6 @@ export class PlannerAgent extends BaseAgent {
     }
   }
 
-  // ---------------------------------------------------------------------------
-  // Structural skill injection (v10)
-  // Translates writing methodology into concrete mustKeep/styleEmphasis rules.
-  // ---------------------------------------------------------------------------
-
-  private injectStructuralSkills(params: {
-    chapterNumber: number;
-    language: string;
-    platform: string;
-    mustKeep: string[];
-    mustAvoid: string[];
-    styleEmphasis: string[];
-    hookAgenda: { eligibleResolve: ReadonlyArray<string> };
-    cadence: ReturnType<typeof analyzeChapterCadence>;
-  }): void {
-    const ch = params.chapterNumber;
-    const isEn = params.language === "en";
-    const isTomato = params.platform === "tomato";
-
-    // S01: 黄金开篇
-    const goldenLimit = isEn ? 5 : 3;
-    const goldenRulesZh: Record<number, string> = {
-      1: "【黄金第1章】直接进入冲突场景，禁止背景介绍开头。第一段必须有动作或对话。核心矛盾本章浮出水面。最多2个场景3个角色。",
-      2: "【黄金第2章】主角的金手指/核心能力必须初现，通过具体事件展现。第一个小爽点在本章出现。继续收紧核心冲突，不引入新支线。",
-      3: "【黄金第3章】明确具体可衡量的短期目标（打败某人/获得某物/到达某处）。章尾钩子要最强——这是读者决定是否追读的关键章。",
-    };
-    const goldenRulesEn: Record<number, string> = {
-      1: "[Golden Ch1] Drop into conflict — no worldbuilding preamble. First paragraph: action or dialogue. Core conflict surfaces. Max 2 scenes, 3 characters.",
-      2: "[Golden Ch2] Reveal protagonist's edge through a concrete event. First small payoff lands. Tighten core conflict, no new subplots.",
-      3: "[Golden Ch3] Lock in a specific measurable short-term goal. Strong chapter-end hook — make-or-break for retention.",
-      4: "[Golden Ch4] First MAJOR payoff — reward reader investment. Raise emotional stakes: what protagonist stands to LOSE becomes clear.",
-      5: "[Golden Ch5] Raise stakes before paywall — new threat/complication. World expands. Strongest cliffhanger yet — conversion chapter.",
-    };
-    if (ch <= goldenLimit) {
-      const rule = isEn ? goldenRulesEn[ch] : goldenRulesZh[ch];
-      if (rule) params.mustKeep.push(rule);
-    }
-
-    // S02: 付费卡点 / 留存生死线
-    if (isTomato) {
-      // 番茄：免费模式，前3章是编辑签约+读者留存的生死线（和S01重叠）
-      // 不需要额外规则，S01已覆盖
-    } else if (isEn) {
-      // GoodNovel/Dreame：第6-8章付费墙
-      if (ch >= 5 && ch <= 8) {
-        params.mustKeep.push("[Paywall Zone] Reader hits paywall soon — chapter MUST end with an irresistible cliffhanger that makes paying feel inevitable.");
-      }
-    }
-
-    // S04: 日常段服务主线
-    if (params.cadence.moodPressure?.pressure !== "high") {
-      params.styleEmphasis.push(isEn
-        ? "If this chapter has quiet/daily scenes, each must plant a hook or advance a relationship — no pure filler. Every daily scene is bait for the main plot."
-        : '如果本章有日常/过渡段，每段必须埋伏笔或推关系。万物皆为主线的"饵"，纯填充即流水账。');
-    }
-
-    // S03: 情绪升压（补充已有的降调逻辑）
-    // 已有 moodDirective 处理连续高压→降调。这里处理反向：无压力时提醒升压
-    if (!params.cadence.moodPressure && ch > goldenLimit) {
-      params.styleEmphasis.push(isEn
-        ? "Recent chapters have been quiet — this chapter needs to escalate tension. Introduce a complication, confrontation, or revelation."
-        : "最近几章情绪偏平，本章必须升压——引入新冲突、对抗或揭秘。");
-    }
-
-    // S10+S11: 信息落差 + 欲望驱动（结合 hook 回收时机）
-    if (params.hookAgenda.eligibleResolve.length > 0) {
-      params.styleEmphasis.push(isEn
-        ? "A major hook is ready to resolve — maximize tension BEFORE the payoff. The release must exceed reader expectations. Satisfy 70% = failure."
-        : "有伏笔即将兑现——在兑现前把压制拉到最大。释放时必须超过读者预期，只满足70%等于失败。");
-    }
-  }
 }
 
 function extractBalancedJsonObject(text: string): string | null {