fix(code-highlighter): make light-theme colors fully self-contained

[cc-hearts]

🤔 This is a ...

• 🐞 Bug fix

🔗 Related Issues

• Follow-up to fix(code-highlighter): 修复暗色主题下未高亮代码为黑色文字，并将硬编码色 token 化 #172 (fix(code-highlighter): 修复暗色主题下未高亮代码为黑色文字，并将硬编码色 token 化), which tokenized the dark-theme colors but left most of the light-theme side on algorithm-driven global tokens.

💡 Background and Solution

The -light / -dark variants are self-contained color schemes driven by the user-controlled theme prop, so their colors must not follow the app color algorithm - this is the principle #172 established ("using colorText would break the mirrored case"). #172 only tokenized the dark side (plus the line-number light token in the first commit here); the rest of the light chrome still used global tokens.

Impact of the gap - in the mirrored case (app on the dark algorithm + theme="light"), the global tokens resolve to dark-algorithm values:

Global token (light rule)	Light algo	Dark algo (mirrored)	Result on #fafafa
colorTextSecondary (lang label, buttons)	rgba(0,0,0,0.65)	rgba(255,255,255,0.65)	invisible text/icons
colorTextQuaternary (line numbers)	rgba(0,0,0,0.25)	rgba(255,255,255,0.25)	invisible line numbers
colorFillSecondary (header bg)	rgba(0,0,0,0.06)	rgba(255,255,255,0.12)	header loses separation
colorBorderSecondary (borders)	#f0f0f0	dark-algo value	wrong borders

And the dark-theme root border used the global colorBorder instead of codeBorderColorDark, so in the opposite mirrored case (light algorithm + theme="dark") it drew a light #d9d9d9 outline around the dark card.

Solution

Add the missing light counterparts to the existing dark tokens and wire them in, so -light / -dark are now fully self-contained and symmetric:

New light token	Replaces	Dark counterpart (existing)
codeLineNumberColor	colorTextQuaternary	codeLineNumberColorDark
codeHeaderBg	colorFillSecondary	codeHeaderBgDark
codeBorderColor	colorBorderSecondary (root / header-bottom / gutter-right)	codeBorderColorDark
codeLangColor	colorTextSecondary	codeLangColorDark
codeBtnColor	colorTextSecondary	codeBtnColorDark
codeBtnHoverBg	(light had no hover override)	codeBtnHoverBgDark

Also: dark root border colorBorder -> codeBorderColorDark; light action buttons now mirror the dark side with !important + explicit hover background (the dark side already needed !important to beat antd Button .ant-btn-variant-text color).

Defaults preserve the previous common-case appearance - opaque hexes are the equivalent of the prior translucent global tokens composited over white (e.g. #f0f0f0 == colorBorderSecondary / colorFillSecondary over white), and the rgba text colors match the prior colorTextSecondary / colorTextQuaternary under the light algorithm. No visual change in the common case; only the mirrored cases are fixed.

📝 Change Log

Language	Changelog
🇺🇸 English	Fix CodeHighlighter rendering in the mirrored case (app color algorithm opposite to the component theme prop): line numbers, language label, and action buttons were invisible, the header lost separation, and borders were wrong. All light-theme colors are now self-contained component tokens (codeHeaderBg, codeBorderColor, codeLangColor, codeBtnColor, codeBtnHoverBg, codeLineNumberColor) matching the existing dark counterparts; the dark root border now reuses codeBorderColorDark.
🇨🇳 Chinese	修复 CodeHighlighter 在镜像场景（应用算法与组件 theme 相反）下的显示：行号、语言标签、操作按钮不可见，头部背景与内容区糊在一起，边框颜色错误。亮色主题所有颜色改为自包含的组件 token（codeHeaderBg、codeBorderColor、codeLangColor、codeBtnColor、codeBtnHoverBg、codeLineNumberColor），与已有暗色 token 一一对应；暗色根边框改用 codeBorderColorDark。