feat: initial m3ta-home structure

- flake.nix with nixpkgs, home-manager, nix-colors, m3ta-nixpkgs, agenix, NUR inputs
- lib/mkHome.nix: compose HM config from user + identity + context + sets
- profiles/base: shell, cli-tools, secrets (always loaded)
- profiles/contexts/desktop: WM, apps, theme, ghostty
- profiles/contexts/server: minimal headless
- profiles/sets/coding: core (git, direnv, jq, rg), editor, lsp, languages, agents
- profiles/sets/gaming: steam, gamescope, gpu
- profiles/sets/media: obs, ffmpeg, kdenlive, handbrake, yt-dlp
- users/m3tam3re/identities: private.nix, work.nix (git, jj, ssh per identity)
- users/m3tam3re/preferences: cliphist, difftastic, base packages

profiles/base/default.nix

@@ -0,0 +1,68 @@
+# profiles/base/default.nix — Always loaded on every host.
+#
+# Provides:
+#   - nixpkgs overlays and config (unfree, nix-colors, m3ta-nixpkgs)
+#   - Shell (nushell, fish, starship) with enable options
+#   - CLI tools (bat, carapace, direnv, eza, fzf, lf, nitch, television, zellij, zoxide)
+#   - Secrets management (pass-wayland)
+#   - Base packages (libgtop)
+{
+  inputs,
+  lib,
+  outputs,
+  pkgs,
+  system,
+  ...
+}: {
+  imports = [
+    inputs.nix-colors.homeManagerModules.default
+    inputs.m3ta-nixpkgs.homeManagerModules.default
+
+    ./shell
+    ./cli-tools
+    ./secrets
+  ];
+
+  # ── nixpkgs configuration ──
+  nixpkgs = {
+    overlays = [
+      outputs.overlays.temp-packages
+      outputs.overlays.stable-packages
+      outputs.overlays.locked-packages
+      outputs.overlays.pinned-packages
+      outputs.overlays.master-packages
+
+      inputs.nur.overlays.default
+      inputs.m3ta-nixpkgs.overlays.default
+      inputs.m3ta-nixpkgs.overlays.modifications
+      (outputs.lib.mkLlmAgentsOverlay system)
+    ];
+    config = {
+      allowUnfree = true;
+      allowUnfreePredicate = _: true;
+    };
+  };
+
+  # ── Nix settings ──
+  nix = {
+    package = lib.mkDefault pkgs.nix;
+    settings = {
+      experimental-features = ["nix-command" "flakes"];
+      warn-dirty = false;
+    };
+  };
+
+  # ── Color scheme ──
+  colorScheme = inputs.nix-colors.colorSchemes.dracula;
+
+  # ── Base packages ──
+  home.packages = with pkgs; [
+    libgtop
+  ];
+
+  # ── Home Manager self-management ──
+  programs.home-manager.enable = true;
+
+  # ── Default home state version ──
+  home.stateVersion = lib.mkDefault "26.05";
+}