README: index primers/ and us_market/ in the document map

Adds reading-order entries and marks EN-only docs as awaiting
translation.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

README.md

@@ -18,9 +18,41 @@ re-verification before external use.
 
 ## Document map 文档地图
 
-Every document exists in both languages (`_en` / `_zh`), with matching
+Documents exist in both languages (`_en` / `_zh`) with matching section
-section structure so the two versions can be read side by side.
+structure so the two versions can be read side by side; docs marked
-每份文档均有英文与中文两个版本（`_en` / `_zh`），章节结构一一对应，可对照阅读。
+**EN only** are awaiting translation.
+文档以英文与中文两个版本并存（`_en` / `_zh`），章节结构一一对应，可对照阅读；
+标注 **EN only** 的文档中文版待补。
+
+### `primers/` — Background primers 背景入门读物
+
+Market-neutral educational material — no venture-specific analysis.
+与具体业务无关的背景知识读物。
+
+**`primers/grid/` — the grid & markets series 电网与市场系列** (read in order 按序阅读):
+
+| # | EN | 中文 | Contents 内容 |
+|---|---|---|---|
+| 01 | [01_how_the_grid_works_en.md](primers/grid/01_how_the_grid_works_en.md) | [zh](primers/grid/01_how_the_grid_works_zh.md) | Grid physics, the balancing act, blackouts — from first principles. 电网物理原理、实时平衡与停电机理。 |
+| 02 | [02_us_electricity_markets_en.md](primers/grid/02_us_electricity_markets_en.md) | [zh](primers/grid/02_us_electricity_markets_zh.md) | How US wholesale markets are organized. 美国批发电力市场结构。 |
+| 03 | [03_china_electricity_markets_en.md](primers/grid/03_china_electricity_markets_en.md) | [zh](primers/grid/03_china_electricity_markets_zh.md) | China's market structure and reform path. 中国电力市场结构与改革路径。 |
+| 04 | [04_market_mechanics_companion_en.md](primers/grid/04_market_mechanics_companion_en.md) | [zh](primers/grid/04_market_mechanics_companion_zh.md) | Market mechanics companion — clearing, pricing, settlement. 市场机制手册——出清、定价、结算。 |
+| 05 | [05_trading_under_uncertainty_en.md](primers/grid/05_trading_under_uncertainty_en.md) | [zh](primers/grid/05_trading_under_uncertainty_zh.md) | Trading under uncertainty. 不确定性下的交易。 |
+
+**Topical primers 专题读物** (EN only):
+
+| Doc 文档 | File | Contents 内容 |
+|---|---|---|
+| SCUC & SCED | [scuc_sced_en.md](primers/scuc_sced_en.md) | The two optimization problems that clear US wholesale markets; N-1 security, LMP as dual variables. 出清美国批发市场的两大优化问题。 |
+| Newsvendor 报童模型 | [newsvendor_en.md](primers/newsvendor_en.md) | The newsvendor problem applied to electricity bidding — underpins the bid loop in `pjm/design_models_*`. 报童模型在电力竞价中的应用。 |
+| Stochastic optimization 随机优化 | [stochastic_optimization_en.md](primers/stochastic_optimization_en.md) | Stochastic optimization in power systems — scenarios, recourse, hydro, offering under uncertainty. 电力系统中的随机优化。 |
+
+### `us_market/` — US market reference 美国市场综述
+
+| Doc 文档 | EN | 中文 | Contents 内容 |
+|---|---|---|---|
+| Field guide 实务指南 | [field_guide_en.md](us_market/field_guide_en.md) | EN only | Bidding, trading, and the impact of AI — consolidated working discussions, July 2026. 竞价、交易与 AI 影响综合笔记。 |
+| Economists survey 经济学家综述 | [economists_survey_en.md](us_market/economists_survey_en.md) | [economists_survey_zh.md](us_market/economists_survey_zh.md) | How economists shaped US electricity markets — theory, practice, milestones. 经济学家如何塑造美国电力市场——理论、实践与里程碑。 |
 
 ### `pjm/` — US market 美国市场
 
@@ -39,10 +71,11 @@ section structure so the two versions can be read side by side.
 
 ## Suggested reading order 建议阅读顺序
 
-1. **New to PJM 不熟悉 PJM** → `pjm/market_primer_*` → `pjm/design_models_*`
+1. **New to power markets entirely 电力市场零基础** → `primers/grid/01–05` in order 按序阅读
-2. **New to China's market 不熟悉中国市场** → `china/market_vendor_dd_*` §1 → `china/product_design_*`
+2. **New to PJM 不熟悉 PJM** → `pjm/market_primer_*` → `pjm/design_models_*`
-3. **Business/competitive view 商业与竞争视角** → the two vendor DD docs 两份供应商尽调 → synthesis sections 综合研判章节
+3. **New to China's market 不熟悉中国市场** → `china/market_vendor_dd_*` §1 → `china/product_design_*`
-4. **Modeling 建模视角** → `pjm/design_models_*` (A–C + newsvendor) → `china/product_design_*` (Model D math)
+4. **Business/competitive view 商业与竞争视角** → the two vendor DD docs 两份供应商尽调 → synthesis sections 综合研判章节
+5. **Modeling 建模视角** → `primers/newsvendor_en.md` + `primers/stochastic_optimization_en.md` → `pjm/design_models_*` (A–C + newsvendor) → `china/product_design_*` (Model D math)
 
 ## Conventions 体例约定