v4.0.0 - Templates API

v4.0.0

Breaking changes

• templates is now the API. The flat htmlPath / jsReplacement options are
  removed; passing either throws a migration error. Describe html via
  templates: [{ name, htmlPath, token }]. Pure-JS and pure-CSS builds pass no
  templates. See docs/v4.0.0.md for the full migration guide.
• HTML outputs are a named map. The result now exposes html[name] (each
  { name, path, getHtml }) keyed by template name. The v3.5.0 htmls[] array and
  the getHtml() / htmlPath shorthands are removed.
• Per-template CSS overrides. A template may supply its own cssPath (and
  cssLinkHref), falling back to the shared top-level values. The shared cssPath
  remains the canonical output css file.
• Explicit outputDir validation. build() now throws upfront when outputDir
  does not exist or is not a directory, instead of failing with ENOENT on the first
  write. The library still never creates or cleans directories — that stays the
  caller's responsibility.
• Documented constraint: tokens must be unique in the source file. The injector
  replaces the first occurrence of each token; a token string also present in a comment
  or other literal redirects injection there.

Unchanged from v3.5.0

• Syntax-aware (acorn) injection: markup is spliced into the token's string/template
  literal with escaping for that quote context — safe with quotes, backticks, ${,
  and backslashes in the payload.
• Output-filename collision detection (duplicate resolved names throw).
• Multi-template support; shared css/link are embedded in the first template that uses them by default (sharedMultiTemplate: "first"), or in every template with sharedMultiTemplate: "every".

Migration example

 const result = await build(outputDir, {
   jsPath: '/…/component.js',
   cssPath: '/…/component.css',
-  htmlPath: '/…/index.html',
-  jsReplacement: '__JS_REPLACEMENT__'
+  templates: [
+    { name: 'index', htmlPath: '/…/index.html', token: '__JS_REPLACEMENT__' }
+  ]
 });

-await result.getHtml();
+await result.html.index.getHtml();

What's Changed

• @4.0.0 - templates API by @localnerve in #79

Full Changelog: v3.5.1...v4.0.0