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/sets/media/default.nix

@@ -0,0 +1,10 @@
+# Media profile aggregator — OBS, FFmpeg, yt-dlp, Kdenlive, and HandBrake.
+{...}: {
+  imports = [
+    ./obs.nix
+    ./ffmpeg.nix
+    ./yt-dlp.nix
+    ./kdenlive.nix
+    ./handbrake.nix
+  ];
+}

profiles/sets/media/ffmpeg.nix

@@ -0,0 +1,24 @@
+# FFmpeg — full-featured multimedia processing toolchain.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; let
+  cfg = config.profiles.media.ffmpeg;
+in {
+  options.profiles.media.ffmpeg.enable = mkEnableOption "enable FFmpeg tools";
+
+  config = mkIf cfg.enable {
+    home.packages = with pkgs; [
+      amf
+      ffmpeg_6-full
+      gst_all_1.gstreamer
+      gst_all_1.gst-vaapi
+      pamixer
+      pavucontrol
+      qpwgraph
+    ];
+  };
+}

profiles/sets/media/handbrake.nix

@@ -0,0 +1,21 @@
+# HandBrake — open-source video transcoder.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; let
+  cfg = config.profiles.media.handbrake;
+in {
+  options.profiles.media.handbrake.enable = mkEnableOption "enable HandBrake transcoder";
+
+  config = mkIf cfg.enable {
+    home.packages = with pkgs; [
+      handbrake
+      gimp
+      inkscape
+      libation
+    ];
+  };
+}

profiles/sets/media/kdenlive.nix

@@ -0,0 +1,16 @@
+# Kdenlive — KDE non-linear video editor.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; let
+  cfg = config.profiles.media.kdenlive;
+in {
+  options.profiles.media.kdenlive.enable = mkEnableOption "enable Kdenlive video editor";
+
+  config = mkIf cfg.enable {
+    home.packages = [pkgs.kdePackages.kdenlive];
+  };
+}

profiles/sets/media/obs.nix

@@ -0,0 +1,21 @@
+# OBS Studio — open broadcaster software for streaming and recording.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; let
+  cfg = config.profiles.media.obs;
+in {
+  options.profiles.media.obs.enable = mkEnableOption "enable OBS Studio";
+
+  config = mkIf cfg.enable {
+    home.packages = with pkgs; [
+      v4l-utils
+    ];
+
+    # OBS is managed via NixOS programs.obs-studio at the system level.
+    # Home-manager only installs supporting tools.
+  };
+}

profiles/sets/media/yt-dlp.nix

@@ -0,0 +1,32 @@
+# yt-dlp and media playback — YouTube downloader with MPV integration.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; let
+  cfg = config.profiles.media.ytDlp;
+in {
+  options.profiles.media.ytDlp.enable = mkEnableOption "enable yt-dlp and media playback";
+
+  config = mkIf cfg.enable {
+    home.packages = with pkgs; [
+      plexamp
+      unimatrix
+      webcord
+    ];
+
+    programs.mpv = {
+      enable = true;
+      bindings = {
+        WHEEL_UP = "seek 10";
+        WHEEL_DOWN = "seek -10";
+      };
+      config = {
+        profile = "gpu-hq";
+        ytdl-format = "bestvideo+bestaudio";
+      };
+    };
+  };
+}