feat: add page post type

[rmdes]

Fixes #954. Stacked on #951 (the first commit here is that PR’s): a page is recognised by its h=page vocabulary, so this only works once that lands.

The package

packages/post-type-page follows the other post-type packages: name: "Page", h: "page", fields name and content (required), summary, category, post-status, visibility; an icon; README; docs page and sidebar entry under Post types → Official plug-ins. Not added to the default post types.

Presets

Each preset gets a page case with no date and no collection, at a path each generator serves at /{slug} without configuration:

Preset	post.path	post.url
Eleventy	{slug}.md	{slug}
Hugo	content/{slug}.md	{slug}
Jekyll	{slug}/index.md	{slug}

Media under media/pages/ (Hugo: static/pages/, served at pages/).

Tests

• Preset unit tests: a page entry in each fixture with the paths above (all three fail on main with the dated collection path).
• endpoint-micropub integration: with @indiekit/post-type-page and @indiekit/preset-eleventy installed, h=page&name=About&content=… answers 202 with Location: https://website.example/about.

One thing I noticed while writing that test: Indiekit.postTypes is a single Map that a preset walks in its own init(), so a post type listed after the preset in plugins gets no paths (501 “No configuration provided for page post type”). The test lists the page type first. That affects every add-on post type, not only this one; I can open a separate issue if you’d like it addressed.

Verified locally: preset-eleventy 9/9, preset-jekyll 9/9, preset-hugo 12/12, endpoint-micropub 151/151; eslint and prettier clean.

[paulrobertlloyd]

This is fantastic, thank you. Made a few changes:

• Updated design of post type icon (I really want to update the design of all of these, but made it more consistent with the other post type icons for now)
• Added a page icon
• Added this plugin into the root indiekit.config.js for easier testing
• Added your name and website to the contributors field in package.json, as seems only fair. Let me know if you want me to change that.

[rmdes]

Yay my first plugin contribution is in, I'm so happy 😁