Use the Luanti name in places where forgotten (#600)

docs/luanti_client.md

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+# Luanti's use of the API
+
+This document explains how Luanti's ContentDB client interacts with ContentDB.
+This is useful both for implementing your own client for ContentDB to install mods, 
+or for implementing ContentDB compatible servers.
+
+## Package List API call
+
+The client makes a single [API](https://content.luanti.org/help/api/) request to `/api/packages/`.
+
+The query arguments will include a list of supported types, the current
+[engine version](https://content.luanti.org/api/minetest_versions/),
+and any hidden [Content Flags](https://content.luanti.org/help/content_flags/).
+
+Example URL:
+<https://content.luanti.org/api/packages/?type=mod&type=game&type=txp&protocol_version=39&engine_version=5.3.0&hide=nonfree&hide=desktop_default>
+
+Example response:
+
+```json
+[
+    {
+        "author": "Warr1023",
+        "name": "nodecore",
+        "release": 1234,
+        "short_description": "A short description",
+        "thumbnail": "https://content.luanti.org/thumbnails/1/abcdef.jpg",
+        "title": "NodeCore",
+        "type": "game"
+    }
+]
+```
+
+`thumbnail` is optional, but all other fields are required. 
+
+`type` is one of `mod`, `game`, or `txp`.
+
+`release` is the release ID. Newer releases have higher IDs.
+Luanti compares this ID to a locally stored version to detect whether a package has updates.
+
+Because the client specifies the engine version information, the response must contain a release
+number and the package must be downloadable.
+
+## Screenshots
+
+The client can simply download the URL mentioned in `thumbnail`.
+
+## Downloading and installing
+
+The client downloads packages by constructing a URL for the release and downloading it:
+
+```
+https://content.luanti.org/packages/<author>/<name>/releases/<release>/download/
+```
+
+This supports redirects.
+
+The client will edit the .conf of the installed content to add `author`, `name`, and `release` to
+track the installed release to detect updates in the future.
+
+## Resolving Dependencies
+
+### Short version
+
+Luanti uses `/api/packages/<author>/<name>/dependencies/?only_hard=1` to find out the hard
+dependencies for a package.
+
+Then, it resolves each dependency recursively. 
+
+Say you're resolving for `basic_materials`, then it will attempt to find the mod in this order:
+
+1. It first checks installed mods in the game and mods folder (ie: `mods/basic_materials/`)
+2. Then it looks on ContentDB for exact name matches (ie: `VanessaE/basic_materials`)
+3. Then it looks on ContentDB for modpacks which contain (=provides) the modname
+   (ie: `VanessaE/dreambuilder`)
+
+### Long version
+
+When installing a package, an API request is made to ContentDB to find out the dependencies.
+If there are no dependencies, then the mod is installed straight away.
+
+If there are dependencies, it will resolve them and show a dialog with a list of mods to install.
+
+Resolving works like this:
+
+1. Fetch dependencies for the package from ContentDB's API
+2. For each hard dependency:
+    1. Check current game, exit if dep found
+    2. Check installed mods, exit if found
+    3. Check available mods from ContentDB:
+        1. Choose a package to install. Prefer higher scores and exact base name matches
+           (rather than modpacks).
+        2. Resolve dependencies for this package - ie, goto 1.
+
+The ContentDB API is a dictionary of packages to dependencies.
+The dictionary will allow ContentDB to prefetch dependencies without any client changes.
+For example, say you request the dependencies for Mobs Monster.
+It's pretty likely that the next request you'll make is for Mobs Redo, and so ContentDB can prevent
+the need for another request by including the dependency information for Mobs Redo in the
+response for Mobs Monster.
+
+## View in browser
+
+The client will open the package in a browser by constructing the following URL
+
+```
+https://content.luanti.org/packages/<author>/<name>/
+```