feat(wasm-plugin-system): major overhaul and some goodies

[imsnif]

Intro

While after this there's still some major work that needs to be done for the plugin system, this PR makes developing Rust plugins possible for the pioneering developer. More details will be given upon release in the documentation.

All changes in this PR

Strider now has a Fuzzy Find for file names (and contents!)

2023-05-22_09-39-11.mp4

This is included as a sort of "hidden feature", mainly for the purposes of being a proof of concept for a complex plugin. This feature uses the plugin workers to offload heavy work from the update/render loop. Namely scanning the HD (which is a bit slow with wasmer 2.X, but will be addressed in a future PR) and doing the actual search.

It also uses the new plugin API methods mentioned below to open a file in the user's $EDITOR (to the relevant line), tiled or floating, and also to open a new terminal pane to the file's location (tiled or floating).

It's a bit rough (being mostly a POC), but I personally plan to use it. To access it, open Strider and type / followed by your search term.

When a plugin crashes it no longer crashes Zellij

Instead, we'll display a stack trace on the plugin pane (as well as in the logs) as seen in the above screenshot. (Thanks @har7an for the nice cross-wasm-boundary stack traces).

Plugin workers stay alive

The register_worker macro in zellij-tile now also accepts a static variable where it will store its state. This means that the workers stay alive and don't need to serialize themselves to the HD. It also means that we don't constantly spawn extra async tasks when sending them messages and waiting on them. Which improves performance quite a bit.

New Plugin API methods

• open_file_floating - like the existing open_file but floating - opens the user's $EDITOR to the specified file in a new pane, but in a new floating pane
• open_file_with_line, open_file_with_line_floating - open's the user's $EDITOR to the specified file (and line, if the editor supports it - most do) in either a new tiled or floating pane
• open_terminal, open_terminal_floating - open a new terminal pane (tiled or floating) to the specified CWD

New Plugin Events

Plugins can now subscribe to four file system events (in the folder Zellij was started from): FileSystemCreate(paths), FileSystemRead(paths), FileSystemUpdate(paths), FileSystemDelete(paths)

New CLI Action LaunchOrFocusPlugin

This CLI (or keybind) action will accept a plugin path (either a built-in Zellij plugin or a static path on the HD to a wasm file) and then either focus a pane with this plugin if it is already loaded or open a pane (tiled or floating) and load the plugin inside it.

This is useful for "kiosk" like plugins that appear for a certain task and then hide themselves (eg. the Strider fuzzy file search above) - eg. pressing F1 will load or focus said plugin.