Refactor Library

The launcher code was in a position ripe for sphagetti, so this rewrites it in a more robust way.
In addition to cleaner code, this provides the following changes:
- Removal of obsolete Mojang authentication
- The rebasing of some internal state into a Sled database
- Tweaks which make some internal mechanisms more robust (e.g. profiles which fail to load can be removed)
- Additional tooling integration such as direnv
- Distinct public API to avoid messing with too much internal code
- Unified error handling in the form of `theseus::Error` and `theseus::Result`

flake.nix

@@ -14,7 +14,7 @@
     };
   };
 
-  outputs = inputs:
+  outputs = inputs@{self, ...}:
     inputs.utils.lib.eachDefaultSystem (system: let
       pkgs = import inputs.nixpkgs { inherit system; };
       fenix = inputs.fenix.packages.${system};
@@ -32,13 +32,15 @@
 
       deps = with pkgs; {
         global = [
-          openssl pkg-config
+          openssl pkg-config gcc
         ];
         gui = [
-          gtk4 gdk-pixbuf atk webkitgtk
+          gtk4 gdk-pixbuf atk webkitgtk dbus
         ];
         shell = [
-          toolchain fenix.default.clippy git
+          toolchain
+          (with fenix; combine [toolchain default.clippy rust-analyzer])
+          git
           jdk17 jdk8
         ];
       };
@@ -53,8 +55,22 @@
       };
 
       apps = {
-        theseus-cli = utils.mkApp {
-          drv = inputs.self.packages.${system}.theseus-cli;
+        cli = utils.mkApp {
+          drv = self.packages.${system}.theseus-cli;
+        };
+        cli-test = utils.mkApp {
+          drv = pkgs.writeShellApplication {
+            name = "theseus-test-cli";
+            runtimeInputs = [
+              (self.packages.${system}.theseus-cli.overrideAttrs (old: old // {
+                release = false;
+              }))
+            ];
+            text = ''
+              DUMMY_ID="$(printf '%0.sa' {1..32})"
+              theseus_cli profile run -t "" -n "Test" -i "$DUMMY_ID" "$@"
+            '';
+          };
         };
       };
 
@@ -62,5 +78,5 @@
         buildInputs = with deps;
           global ++ gui ++ shell;
       };
-    });
+    })
 }