feat(mc): add midnight commander with declarative config

Public baseline module: installs `mc` plus `ouch` (backs the F2 pack/unpack
entries, archive format inferred from the extension), and ships `ini`, `menu`,
and a generated `panels.ini` into `$XDG_CONFIG_HOME/mc`.

`local.mc.otherDir` exposes the other-panel start dir as an option defaulting
to `config.home.homeDirectory`, so the one personal value isn't baked in. The
F2 user menu is trimmed to the entries that match this config (imv/zathura/mpv
openers, ouch pack/unpack, man view); the stock rcp/uudecode/news/latex cruft
is dropped. `auto_save_setup=false` keeps mc from rewriting the read-only store
symlinks on exit.

modules/assets/mc/ini

@@ -0,0 +1,160 @@
+[Midnight-Commander]
+verbose=true
+shell_patterns=true
+auto_save_setup=false
+preallocate_space=false
+auto_menu=false
+use_internal_view=true
+use_internal_edit=false
+clear_before_exec=true
+confirm_delete=true
+confirm_overwrite=true
+confirm_execute=false
+confirm_history_cleanup=true
+confirm_exit=false
+confirm_directory_hotlist_delete=false
+confirm_view_dir=false
+safe_delete=false
+safe_overwrite=false
+use_8th_bit_as_meta=false
+mouse_move_pages_viewer=true
+mouse_close_dialog=false
+fast_refresh=false
+drop_menus=false
+wrap_mode=false
+old_esc_mode=true
+cd_symlinks=true
+show_all_if_ambiguous=true
+use_file_to_guess_type=true
+alternate_plus_minus=false
+only_leading_plus_minus=true
+show_output_starts_shell=false
+xtree_mode=false
+file_op_compute_totals=true
+classic_progressbar=true
+use_netrc=true
+ftpfs_always_use_proxy=false
+ftpfs_use_passive_connections=true
+ftpfs_use_passive_connections_over_proxy=false
+ftpfs_use_unix_list_options=true
+ftpfs_first_cd_then_ls=true
+ignore_ftp_chattr_errors=true
+editor_fill_tabs_with_spaces=false
+editor_return_does_auto_indent=true
+editor_backspace_through_tabs=false
+editor_fake_half_tabs=true
+editor_option_save_position=true
+editor_option_auto_para_formatting=false
+editor_option_typewriter_wrap=false
+editor_edit_confirm_save=true
+editor_syntax_highlighting=true
+editor_persistent_selections=true
+editor_drop_selection_on_copy=true
+editor_cursor_beyond_eol=false
+editor_cursor_after_inserted_block=false
+editor_visible_tabs=true
+editor_visible_spaces=true
+editor_line_state=false
+editor_simple_statusbar=false
+editor_check_new_line=false
+editor_show_right_margin=false
+editor_group_undo=false
+editor_state_full_filename=false
+editor_ask_filename_before_edit=false
+nice_rotating_dash=true
+mcview_remember_file_position=false
+auto_fill_mkdir_name=true
+copymove_persistent_attr=true
+pause_after_run=1
+mouse_repeat_rate=100
+double_click_speed=250
+old_esc_mode_timeout=1000000
+max_dirt_limit=10
+num_history_items_recorded=60
+vfs_timeout=60
+ftpfs_directory_timeout=900
+ftpfs_retry_seconds=30
+fish_directory_timeout=900
+editor_tab_spacing=8
+editor_word_wrap_line_length=72
+editor_option_save_mode=0
+editor_backup_extension=~
+editor_filesize_threshold=64M
+editor_stop_format_chars=-+*\\,.;:&>
+mcview_eof=
+skin=yadt256-defbg
+
+shadows=true
+
+[Layout]
+output_lines=0
+left_panel_size=115
+top_panel_size=0
+message_visible=true
+keybar_visible=true
+xterm_title=true
+command_prompt=true
+menubar_visible=true
+free_space=true
+horizontal_split=false
+vertical_equal=true
+horizontal_equal=true
+
+[Misc]
+timeformat_recent=%d. %b %H:%M
+timeformat_old=%d. %b %Y
+ftp_proxy_host=gate
+ftpfs_password=anonymous@
+display_codepage=UTF-8
+source_codepage=Other_8_bit
+autodetect_codeset=
+clipboard_store=
+clipboard_paste=
+
+[Colors]
+base_color=
+st-256color=
+color_terminals=
+
+[Panels]
+show_mini_info=true
+kilobyte_si=true
+mix_all_files=false
+show_backups=true
+show_dot_files=true
+fast_reload=false
+fast_reload_msg_shown=false
+mark_moves_down=true
+reverse_files_only=true
+auto_save_setup_panels=false
+navigate_with_arrows=true
+panel_scroll_pages=true
+panel_scroll_center=false
+mouse_move_pages=true
+filetype_mode=true
+permission_mode=false
+torben_fj_mode=false
+quick_search_mode=2
+select_flags=6
+
+simple_swap=false
+
+[FindFile]
+file_case_sens=true
+file_shell_pattern=true
+file_find_recurs=true
+file_skip_hidden=false
+file_all_charsets=false
+content_case_sens=true
+content_regexp=false
+content_first_hit=false
+content_whole_words=false
+content_all_charsets=false
+ignore_dirs_enable=true
+ignore_dirs=
+
+[Panelize]
+Geänderte Git-Dateien=git ls-files --modified
+Nach dem Patchen nach Ablehnungen suchen=find . -name \\*.rej -print
+Suche SUID- und SGID-Programme=find . \\( \\( -perm -04000 -a -perm /011 \\) -o \\( -perm -02000 -a -perm /01 \\) \\) -print
+Suche nach *.orig nach dem Patchen=find . -name \\*.orig -print

modules/assets/mc/menu

@@ -0,0 +1,30 @@
+shell_patterns=0
+
+# F2 user menu. Format macros: %f current file · %d current dir · %s tagged
+# files else current · %t tagged files · %D other panel's dir. Full list: mc(1).
+
+c       Pack selected into an archive (ouch — format from the name's extension)
+        NAME=%{Archive name, e.g. stuff.tar.zst}
+        ouch compress %s "$NAME"
+
+x       Unpack archive here (ouch)
+        ouch decompress %f
+
+i       Open file with image viewer (imv)
+        imv %f
+
+I       Open current directory with image viewer (imv)
+        imv %d
+
+p       Open file with document viewer (zathura)
+        zathura %f
+
+v       Play file with mpv
+        mpv %f
+
+V       Play current directory with mpv
+        mpv %d
+
+m       View a man page
+        MAN=%{Enter manual name}
+        %view{ascii,nroff} MANROFFOPT='-c -Tlatin1' MAN_KEEP_FORMATTING=1 man -P cat "$MAN"

modules/home.nix

@@ -71,7 +71,7 @@ let
   '';
 in
 {
-  imports = [ ./gpg.nix ./media.nix ./texlive.nix ./librewolf.nix ];
+  imports = [ ./gpg.nix ./media.nix ./texlive.nix ./librewolf.nix ./mc.nix ];
 
   # Put ~/.local/bin (the XDG user-bin dir) on PATH so hand-dropped scripts run
   # by name without wiring each through nix.

modules/mc.nix

@@ -0,0 +1,72 @@
+# Midnight Commander: TUI file manager. Its config (ini, panels, F2 user menu)
+# is opinionated but generic, so it lives in the public baseline alongside the
+# other desktop tooling. The only personal value is the right-panel start dir,
+# exposed as an option defaulting to the consumer's own home.
+#
+# ouch backs the F2 pack/unpack entries (one tool, archive format inferred from
+# the extension), so it ships with mc to keep the menu self-contained.
+#
+# mc honours XDG natively: config in $XDG_CONFIG_HOME/mc (the files below),
+# mutable runtime state (history, cursor positions) in $XDG_DATA_HOME/mc — no
+# env vars needed. `ini` sets auto_save_setup=false so mc never rewrites these
+# read-only store symlinks on exit.
+
+{ config, lib, pkgs, ... }:
+
+{
+  options.local.mc.otherDir = lib.mkOption {
+    type = lib.types.str;
+    default = config.home.homeDirectory;
+    defaultText = lib.literalExpression "config.home.homeDirectory";
+    description = "Startup directory for mc's other (right) panel.";
+  };
+
+  config = {
+    home.packages = [ pkgs.mc pkgs.ouch ];
+
+    xdg.configFile = {
+      "mc/ini".source = ./assets/mc/ini;
+      "mc/menu".source = ./assets/mc/menu;
+
+      # Generated (not a static asset) so other_dir tracks the option instead of
+      # baking in a personal path.
+      "mc/panels.ini".text = ''
+        [New Left Panel]
+        display=listing
+        reverse=false
+        case_sensitive=true
+        exec_first=false
+        sort_order=name
+        list_mode=full
+        brief_cols=2
+        user_format=half type name | size | perm | mtime
+        user_status0=half type name | size | perm
+        user_status1=half type name | size | perm
+        user_status2=half type name | size | perm
+        user_status3=half type name | owner | group | ctime
+        user_mini_status=true
+        list_format=user
+
+        [New Right Panel]
+        display=listing
+        reverse=false
+        case_sensitive=true
+        exec_first=false
+        sort_order=name
+        list_mode=full
+        brief_cols=2
+        user_format=half type name | size | perm | mtime
+        user_status0=half type name | size | perm
+        user_status1=half type name | size | perm
+        user_status2=half type name | size | perm
+        user_status3=half type name | owner | group | ctime
+        user_mini_status=true
+        list_format=user
+
+        [Dirs]
+        current_is_left=true
+        other_dir=${config.local.mc.otherDir}
+      '';
+    };
+  };
+}