refactor(params)!: flatten [params.page] to [params], snake_case keys, more page-level params support (#805)

* refactor(params)!: snake_case config + eliminate params.page + use .Param

BREAKING CHANGE: All params keys renamed from camelCase to snake_case,
[params.page] section eliminated (moved to [params] level), and users
must update their hugo.toml and front matter accordingly.

Key changes:
- All camelCase config keys → snake_case (e.g., defaultTheme → default_theme)
- [params.page] flat keys and sub-sections moved to [params] level
- Removed function/params.html (manual merge), replaced with Hugo .Param
- New function/param.html partial for page-level section params with
  shorthand boolean support and site defaults merging
- New function/camel-case.html for string conversion
- snake2camel.html renamed to camel-case-keys.html
- New function/get-cover.html for cover image resolution
- Deprecation warnings in detection-deprecated.html for old config keys
- Front matter only params (subtitle, featured_image, password, repost,
  weight, message) use .Params.xxx instead of .Param
- Page-level sections use param.html partial
- Simplified patch.html (siteTime only) and init/index.html

Refs: camel-case-keys.html#29 (planned v1.0 breaking change)

* refactor(params)!: move params.link to page-level, simplify link guard

- Move [params.link] and [params.link.guard] to page-level section
- link.html: .Page optional, use param.html when available for
  page-level override, fall back to site config without .Page
- Remove $guardConfig variable, use $config.guard directly
- Remove unnecessary .Page from callers that don't need page override
- friends.html: use param.html for link guard instead of link_guard

* refactor(params)!: move image/codeblock/json_viewer/filetree to page-level

- Move [params.image], [params.codeblock], [params.json_viewer],
  [params.filetree] to page-level sub-sections
- Templates use param.html for merged config (page override + site defaults)
- image.html: .Page optional, falls back to site config without .Page
- Add v1- prefix to all deprecation warnidf IDs
- Fix camelCase key access in image.html (blackList, cacheRemote)
- Fix Hugo-lowered camelCase keys in code-block-wrapper.html
- Add deprecation warnings for codeblock camelCase Markdown attributes
- Add deprecation warnings for file-tree camelCase Markdown attributes
- Update render-codeblock-toggle.html for snake_case attribute names

* style: standardize @param comment style across all HTML templates

- PascalCase types: {string} → {String}, {boolean} → {Boolean},
  {int} → {Int}, {map} → {Map}, {array} → {Array}
- Add missing ` - ` separator between param name and description
- Remove extra alignment spaces between type and param name

* refactor(params)!: move params.mermaid to page-level, extract gen/ templates

- Move [params.mermaid] to page-level sub-sections
- Mermaid config injected into window.config (per-page override support)
- mermaid.ts reads config from window.config.mermaid instead of parameter
- Create _partials/gen/ directory for JS content generators
- Move mermaid-bootstrap.html from plugin/ to gen/
- Extract window.config JS generation into gen/config.html
- mermaid.html uses param.html for wrapper config

* refactor(params)!: consolidate link_to_* into params.post_link section

- Move link_to_markdown/source/edit/report/vscode into [params.post_link]
- Rename keys: markdown, source, edit, report (bool), editor (string)
- editor defaults to "vscode", supports "trae" etc. via protocol template
- footer.html uses .Param "post_link" for all link toggles
- Remove link_to_* from deprecated keys list

* fix: add fallback for deprecated camelCase attributes and expand deprecation warnings

- render-codeblock-file-tree.html: folderSlash attribute fallback
- render-codeblock-toggle.html: lineNosToggler/lineWrapToggler fallback + warnings
- code-block-wrapper.html: maxShownLines/wrapperClass fallback
- detection-deprecated.html: add nested key warnings for 13 sections
  (header, breadcrumb, navigation, watermark, busuanzi, image, mermaid,
  codeblock, filetree, math.katex, math.mathjax.options, post_summary, footer)
- detection-deprecated.html: add link_guard front matter deprecation warning

* fix(mermaid): fix rendering in hidden tab panels and neutral layer scheduling

- isRenderContextActive: check tab-panel visibility via getBoundingClientRect
  instead of panel.hidden (tab-container uses slot-based hiding, not hidden attr)
- bindTabContainerChanged: render neutral layers when switching tabs so
  print/fallback scenarios work correctly

assets/js/lib/mermaid.ts

@@ -43,13 +43,6 @@ interface RenderOptions {
   darkMode: boolean
 }
 
-interface MermaidBootstrapOptions {
-  mermaidSource: string
-  zenumlSource?: string
-  layoutLoaderSources?: string[]
-  config: MermaidConfig
-}
-
 let mermaid: MermaidRuntimeModule | null = null
 let config: MermaidConfig = {}
 let hasBoundGlobalEvents = false
@@ -179,8 +172,12 @@ function isRenderContextActive(el: Element): boolean {
     return false
 
   const panel = el.closest('.tab-panel')
-  if (panel instanceof HTMLElement && panel.hidden)
-    return false
+  if (panel) {
+    // tab-container uses slot-based hiding; check actual layout visibility
+    const panelRect = panel.getBoundingClientRect()
+    if (panelRect.width === 0 && panelRect.height === 0)
+      return false
+  }
 
   return true
 }
@@ -231,11 +228,11 @@ function ensureMermaidInitialized(theme: string, darkMode: boolean): void {
     startOnLoad: false,
     darkMode,
     theme,
-    securityLevel: config.securitylevel,
+    securityLevel: config.securityLevel,
     look: config.look,
     layout: config.layout,
-    fontFamily: config.fontfamily,
-    altFontFamily: config.fontfamily,
+    fontFamily: config.fontFamily,
+    altFontFamily: config.fontFamily,
   })
 }
 
@@ -271,7 +268,7 @@ async function renderMermaidElement(el: Element | null, options: RenderOptions):
     try {
       const result = await mermaid.render(id, source, el)
       const svg = result?.svg ?? ''
-      el.innerHTML = svg
+      svg && (el.innerHTML = svg)
       if (typeof result?.bindFunctions === 'function') {
         try {
           result.bindFunctions(el)
@@ -681,6 +678,12 @@ function bindTabContainerChanged(): void {
     if (!panel)
       return
     observeMermaidContainers(panel, true)
+    // Also schedule neutral layer render for the newly visible panel
+    const neutralNodes = panel.querySelectorAll<Element>('.mermaid-neutral')
+    neutralNodes.forEach((el) => {
+      if (!el.hasAttribute('data-processed'))
+        void renderMermaidElement(el, { theme: 'neutral', darkMode: false })
+    })
   }, false)
 }
 
@@ -856,10 +859,12 @@ function unwrapModule<T>(mod: { default?: T } | T): T {
 /**
  * Bootstrap entry used by template-injected script.
  * Loads Mermaid and optional extensions via dynamic import and hands runtime to initMermaidRuntime.
- * @param options Bootstrap options provided by template-injected script.
  */
-export async function bootstrapMermaid(options: MermaidBootstrapOptions): Promise<void> {
-  const { mermaidSource, zenumlSource = '', layoutLoaderSources = [], config } = options
+export async function bootstrapMermaid(): Promise<void> {
+  config = window.config?.mermaid ?? {}
+  const mermaidSource = config.cdn || 'https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.esm.min.mjs'
+  const zenumlSource = config.zenuml || ''
+  const layoutLoaderSources = config.layoutLoaders || []
 
   try {
     // Mermaid core module is required; optional modules degrade gracefully.

assets/js/types/third-party.ts

@@ -3,10 +3,10 @@ export interface MermaidConfig {
   cdn?: string
   zenuml?: string
   themes?: string[]
-  securitylevel?: string
+  securityLevel?: string
   look?: string
-  fontfamily?: string
-  layoutloaders?: string[]
+  fontFamily?: string
+  layoutLoaders?: string[]
   layout?: string
 }
 

assets/scss/core/mixins/_media.scss

@@ -1,4 +1,4 @@
-// FixIt Responsive breakpoints system design
+// FixIt responsive breakpoints system design
 // ┌──────┬───────────┬───────────┬──────────────┐
 // │ Name │ min-width │ max-width │ Direction    │
 // ├──────┼───────────┼───────────┼──────────────┤