refactor: reorganize, add package (opencode, osgrep, beads), add ai agent shell

modules/home/devtools/languages.nix

@@ -0,0 +1,127 @@
+{ config, lib, pkgs, ... }:
+let
+  inherit (lib) mkEnableOption mkOption mkIf types warn unique;
+  cfg = config.rsydn.languages;
+
+  hasPkg = name: builtins.hasAttr name pkgs;
+  getPkg = name: if hasPkg name then pkgs.${name} else null;
+
+  mkToolOption = { name, defaultPackage, description }:
+    mkOption {
+      type = types.submodule {
+        options = {
+          enable = mkOption {
+            type = types.bool;
+            default = defaultPackage != null;
+            description = "Enable ${name} tooling globally.";
+          };
+          package = mkOption {
+            type = types.nullOr types.package;
+            default = defaultPackage;
+            description =
+              "Package derivation to install for ${name}. Set to null to skip.";
+          };
+        };
+      };
+      default = {
+        enable = defaultPackage != null;
+        package = defaultPackage;
+      };
+      description = description;
+    };
+
+  mkToolPackages = specs:
+    builtins.concatMap (tool:
+      let toolCfg = tool.cfg;
+      in if toolCfg.enable then
+        if toolCfg.package != null then
+          [ toolCfg.package ]
+        else
+          warn "rsydn.languages.${tool.name}: package is null, skipping" [ ]
+      else
+        [ ]) specs;
+
+  uvPackage = getPkg "uv";
+  goPackage = getPkg "go";
+  nodePackage = if builtins.hasAttr "nodejs_20" pkgs then
+    pkgs.nodejs_20
+  else
+    getPkg "nodejs";
+  cargoPackage = getPkg "cargo";
+  bunPackage = getPkg "bun";
+
+  toolSpecs = [
+    {
+      name = "uv";
+      cfg = cfg.uv;
+      defaultPackage = uvPackage;
+    }
+    {
+      name = "go";
+      cfg = cfg.go;
+      defaultPackage = goPackage;
+    }
+    {
+      name = "node";
+      cfg = cfg.node;
+      defaultPackage = nodePackage;
+    }
+    {
+      name = "cargo";
+      cfg = cfg.cargo;
+      defaultPackage = cargoPackage;
+    }
+    {
+      name = "bun";
+      cfg = cfg.bun;
+      defaultPackage = bunPackage;
+    }
+  ];
+
+  languagePackages = mkToolPackages toolSpecs;
+
+in {
+  options.rsydn.languages = {
+    enable = mkEnableOption "Language tooling packages for everyday workflows";
+
+    uv = mkToolOption {
+      name = "uv";
+      defaultPackage = uvPackage;
+      description = "Python package installer and virtualenv manager.";
+    };
+
+    go = mkToolOption {
+      name = "Go";
+      defaultPackage = goPackage;
+      description = "Go compiler and GOPATH toolchain.";
+    };
+
+    node = mkToolOption {
+      name = "Node.js";
+      defaultPackage = nodePackage;
+      description = "Node.js runtime for CLI tooling.";
+    };
+
+    cargo = mkToolOption {
+      name = "Cargo";
+      defaultPackage = cargoPackage;
+      description = "Rust package manager and toolchain.";
+    };
+
+    bun = mkToolOption {
+      name = "Bun";
+      defaultPackage = bunPackage;
+      description = "Fast all-in-one JavaScript runtime.";
+    };
+
+    extraPackages = mkOption {
+      type = types.listOf types.package;
+      default = [ ];
+      description = "Additional language tooling packages to install globally.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    home.packages = unique (languagePackages ++ cfg.extraPackages);
+  };
+}