feedback6: version 0.2.1 — package.json / package-lock.json / APP_VERSION (DEV_BUILD turns false: the title-screen dev tag, the boot warning and the package guard go)

- CHANGELOG 0.2.1 (2026-10-07): the streams' lines collected (新功能: the update package and MANIFEST.json; 规则（按官方）:
  联防 on the round's battlefield, 突袭 onto a teammate's half, full potential, the replace dialog for consumables,
  the 外勤医疗 Touch, 凋亡, 贾维's 拉普兰德, the 频次 器物 / leader summons; 界面: the collapse arrow, 自选 picks in the bond
  lists, flyers, enemy animations, the Touch card, Esc in the 自选 picker; 联机与大厅: battle messages while a battle
  loads; 工具与开发: the update build, .gitignore), one intro paragraph.
- README: the dev warning under the title removed, the release badge, 「当前版本 0.2.1」; DESIGN's version line names
  0.2.1 (§26) as the state described; §26's intro says when the dev line shipped.
- Tests: version, docs-consistency, docs-paths, package, i18n-packs, update-package, update-boot 80 / 80.

docs/DESIGN.md

@@ -4,7 +4,7 @@ This is the **single source of truth** for every implementer. Research lives in
 
 Language: player-facing text is **Simplified Chinese** by default, with an English switch since 0.2.0 (§25.2, docs/I18N.md: UI strings through `t('中文')`, game texts from the official Chinese data or the official EN client's). Code, comments and identifiers are English.
 
-Versions: the first public release was **0.1.0** (2026-10-02, the state of §0–§20.15); the releases after it add the player feedback and GitHub reports — 0.1.1 §21, 0.1.2 §22, 0.1.3 §23, 0.1.4 §24 — and **0.2.0** (2026-10-07; `CHANGELOG.md`) the maintainability refactor, two languages, 补位, 自选编队 and their fidelity work — §25. The 0.2.1 dev line (`package.json`, `shared/constants.js APP_VERSION`: `0.2.1-dev`) adds §26 and is the state described by this document. The labels v1 / v2 / v2.1–v2.5.2 in §0, §14–§20 and in the BALANCE / SIM comparisons name the design generations and the private playtest builds that came before it; they are kept as history.
+Versions: the first public release was **0.1.0** (2026-10-02, the state of §0–§20.15); the releases after it add the player feedback and GitHub reports — 0.1.1 §21, 0.1.2 §22, 0.1.3 §23, 0.1.4 §24 — and **0.2.0** (2026-10-07; `CHANGELOG.md`) the maintainability refactor, two languages, 补位, 自选编队 and their fidelity work — §25 — and **0.2.1** (2026-10-07; `package.json`, `shared/constants.js APP_VERSION`) the 联防 battlefield restored, full potential and the GitHub fixes after it — §26 — and is the state described by this document. The labels v1 / v2 / v2.1–v2.5.2 in §0, §14–§20 and in the BALANCE / SIM comparisons name the design generations and the private playtest builds that came before it; they are kept as history.
 
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