Add 256-color variants to theme files and consolidate theme loading

Merge the separate default_theme256.toml into default_theme.toml so each
theme file contains both [theme] and [theme256] sections. Add 256-color
variants to both IBM1970 (default) and 42KM themes. Simplify config.rs
to load a single theme file instead of two.

Author: andornaut

README.md

@@ -9,7 +9,7 @@ FileCTRL is a light, opinionated, responsive, theme-able, and simple Text User I
 - Simple interface with good defaults - works out of the box with [sensible settings](#configuration)
 - [Vim-like navigation](#default-keybindings) and [multi-select](#multi-select) - hjkl movement, marks, range mode
 - [Rebindable keys](#customizing-keybindings) - customize all keybindings via TOML config
-- [Customizable colors](#theming) - full truecolor and 256-color theme support with LS_COLORS integration
+- [Customizable colors](#theming) - full truecolor and 256 color theme support with LS_COLORS integration
 - Responsive layout - adapts columns and content to small and large terminal windows
 
 ## Installation
@@ -174,7 +174,7 @@ open_selected_file = "open %s"
 
 ### Theming
 
-FileCTRL supports two theme sections: `[theme]` for truecolor terminals and `[theme256]` for 256-color terminals. At startup, FileCTRL detects truecolor support via the `$COLORTERM` environment variable. Use `--colors-256` to force the 256-color theme.
+FileCTRL supports two theme sections: `[theme]` for truecolor terminals and `[theme256]` for 256-color terminals. At startup, FileCTRL detects truecolor support via the `$COLORTERM` environment variable. Use `--colors-256` to force the 256 color theme.
 
 #### Style properties
 
@@ -191,7 +191,7 @@ All properties are optional. Omit any property to use its default. Set `fg` or `
 **Color formats:**
 
 - **Truecolor** (`[theme]`): hex strings like `"#FF0000"`, or named colors like `"Red"`
-- **256-color** (`[theme256]`): decimal indexes `"0"` through `"255"`
+- **256 color** (`[theme256]`): decimal indexes `"0"` through `"255"`
 
 **Available modifiers:** `"bold"`, `"dim"`, `"italic"`, `"underlined"`, `"blink"`, `"rapid_blink"`, `"reversed"`, `"crossed_out"`
 
@@ -255,7 +255,6 @@ To get started with custom themes, export the built-in defaults as standalone fi
 filectrl --write-default-themes
 # Creates:
 #   ~/.config/filectrl/theme.toml
-#   ~/.config/filectrl/theme256.toml
 ```
 
 Then copy, rename, and edit them:
@@ -289,9 +288,8 @@ FileCTRL includes the following themes in the [`themes/`](themes/) directory:
 
 Theme | Inspired by | Screenshot
 ----- | ----------- | ----------
-[IBM1970](themes/ibm1970.toml) (default) | [vscode-ibm1970-theme](https://github.com/andornaut/vscode-ibm1970-theme) | [![IBM1970](./screenshots/IBM1970.png)](./screenshots/IBM1970.png)
-[42KM](themes/42km.toml) | [vscode-42km-theme](https://github.com/andornaut/vscode-42km-theme) | [![42KM](./screenshots/42KM.png)](./screenshots/42KM.png)
-[256 colors mode](themes/ibm1970-256.toml) (default when run with `--colors-256`) | | [![256 colors](./screenshots/colors256.png)](./screenshots/colors256.png)
+[IBM1970](./themes/ibm1970.toml) (default) | [vscode-ibm1970-theme](https://github.com/andornaut/vscode-ibm1970-theme) | [![IBM1970](./screenshots/IBM1970.png)](./screenshots/IBM1970.png)
+[42KM](./themes/42km.toml) | [vscode-42km-theme](https://github.com/andornaut/vscode-42km-theme) | [![42KM](./screenshots/42KM.png)](./screenshots/42KM.png)
 
 ```bash
 filectrl --include themes/42km.toml

src/app/config.rs

@@ -19,9 +19,7 @@ static CONFIG: OnceLock<Config> = OnceLock::new();
 const CONFIG_RELATIVE_PATH: &str = "config.toml";
 const DEFAULT_CONFIG_BASE: &str = include_str!("config/default_config.toml");
 const DEFAULT_THEME: &str = include_str!("config/default_theme.toml");
-const DEFAULT_THEME256: &str = include_str!("config/default_theme256.toml");
 const DEFAULT_THEME_FILENAME: &str = "theme.toml";
-const DEFAULT_THEME256_FILENAME: &str = "theme256.toml";
 
 #[derive(Debug, Deserialize)]
 pub struct FileSystemConfig {
@@ -155,12 +153,6 @@ impl Config {
         fs::write(&theme_path, DEFAULT_THEME)
             .map_err(|error| anyhow!("Cannot write theme file to {theme_path:?}: {error}"))?;
         info!("Wrote the default theme to {theme_path:?}");
-
-        let theme256_path = dir.join(DEFAULT_THEME256_FILENAME);
-        fs::write(&theme256_path, DEFAULT_THEME256).map_err(|error| {
-            anyhow!("Cannot write 256-color theme file to {theme256_path:?}: {error}")
-        })?;
-        info!("Wrote the default 256-color theme to {theme256_path:?}");
         Ok(())
     }
 
@@ -284,13 +276,12 @@ fn merge_include_paths(mut value: Value, include_paths: &[PathBuf]) -> Result<Va
     Ok(value)
 }
 
-/// Merges the embedded default config from its three source files:
-/// base config + truecolor theme + 256-color theme.
+/// Merges the embedded default config from its two source files:
+/// base config + theme (which includes both truecolor and 256-color variants).
 fn merge_default_config() -> Result<Value> {
     let base = parse_toml(DEFAULT_CONFIG_BASE)?;
     let theme = parse_toml(DEFAULT_THEME)?;
-    let theme256 = parse_toml(DEFAULT_THEME256)?;
-    Ok(merge_toml_values(merge_toml_values(base, theme), theme256))
+    Ok(merge_toml_values(base, theme))
 }
 
 /// Deep-merges two TOML values. Tables are merged recursively;

src/app/config/default_theme.toml

@@ -236,3 +236,242 @@ fg = "#DDDCCC"
 [theme.table.selected]
 bg = "#006B6B"
 fg = "#DDDCCC"
+
+[theme256]
+# 256-color variant of the IBM1970 theme
+bg = "237" # #3a3a3a - dark gray (approx #423F2E)
+fg = "253" # #dadada - light gray (approx #DDDCCC)
+
+[theme256.alert]
+fg = "144" # #afaf87 - olive sage (approx #9C9977)
+
+[theme256.alert.error]
+fg = "160" # #d70000 - red
+
+[theme256.alert.info]
+fg = "106" # #87af00 - green (approx #859900)
+
+[theme256.alert.warn]
+fg = "130" # #af5f00 - rust (approx #b05533)
+
+[theme256.breadcrumbs]
+bg = "236" # #303030 - dark (approx #373424)
+
+[theme256.breadcrumbs.ancestor]
+fg = "253" # #dadada
+
+[theme256.breadcrumbs.basename]
+bg = "30" # #008787 - dark teal (approx #006B6B)
+fg = "253" # #dadada
+modifiers = ["bold"]
+
+[theme256.breadcrumbs.separator]
+fg = "144" # #afaf87 - olive sage (approx #9C9977)
+
+[theme256.clipboard.copy]
+bg = "106" # #87af00 - green (approx #859900)
+fg = "235" # #262626
+
+[theme256.clipboard.cut]
+bg = "136" # #af8700 - amber (approx #B58900)
+fg = "235" # #262626
+
+[theme256.clipboard.delete]
+bg = "130" # #af5f00 - rust (approx #b05533)
+fg = "235" # #262626
+
+[theme256.file_modified_date.less_than_minute]
+fg = "117" # #87d7ff - sky blue (approx #87CEEB)
+
+[theme256.file_modified_date.less_than_hour]
+fg = "51" # #00ffff - cyan
+
+[theme256.file_modified_date.less_than_day]
+fg = "46" # #00ff00 - bright green
+
+[theme256.file_modified_date.less_than_month]
+fg = "226" # #ffff00 - yellow
+
+[theme256.file_modified_date.less_than_year]
+fg = "201" # #ff00ff - magenta
+
+[theme256.file_modified_date.greater_than_year]
+fg = "196" # #ff0000 - red
+
+[theme256.file_size.bytes]
+fg = "117" # #87d7ff - sky blue
+
+[theme256.file_size.kib]
+fg = "51" # #00ffff - cyan
+
+[theme256.file_size.mib]
+fg = "46" # #00ff00 - bright green
+
+[theme256.file_size.gib]
+fg = "226" # #ffff00 - yellow
+
+[theme256.file_size.tib]
+fg = "201" # #ff00ff - magenta
+
+[theme256.file_size.pib]
+fg = "196" # #ff0000 - red
+
+[theme256.file_type]
+ls_colors_take_precedence = false
+
+[theme256.file_type.block_device]
+bg = "230" # #ffffd7
+fg = "244" # #808080
+modifiers = ["bold"]
+
+[theme256.file_type.character_device]
+bg = "230" # #ffffd7
+fg = "244" # #808080
+modifiers = ["bold"]
+
+[theme256.file_type.directory]
+fg = "33" # #0087ff - blue
+
+[theme256.file_type.directory_other_writable]
+bg = "235" # #262626
+fg = "33" # #0087ff
+
+[theme256.file_type.directory_sticky]
+bg = "33" # #0087ff
+fg = "230" # #ffffd7
+
+[theme256.file_type.directory_sticky_other_writable]
+bg = "64" # #5f8700
+fg = "230" # #ffffd7
+
+[theme256.file_type.door]
+bg = "230" # #ffffd7
+fg = "136" # #af8700
+modifiers = ["bold"]
+
+[theme256.file_type.executable]
+fg = "64" # #5f8700
+modifiers = ["bold"]
+
+[theme256.file_type.missing]
+
+[theme256.file_type.normal_file]
+fg = "254" # #e4e4e4
+
+[theme256.file_type.pipe]
+bg = "230" # #ffffd7
+fg = "136" # #af8700
+modifiers = ["bold"]
+
+[theme256.file_type.regular_file]
+fg = "254" # #e4e4e4
+
+[theme256.file_type.setgid]
+bg = "136" # #af8700
+fg = "230" # #ffffd7
+
+[theme256.file_type.setuid]
+bg = "160" # #d70000
+fg = "230" # #ffffd7
+
+[theme256.file_type.socket]
+bg = "230" # #ffffd7
+fg = "136" # #af8700
+modifiers = ["bold"]
+
+[theme256.file_type.symlink]
+fg = "37" # #00afaf - cyan
+modifiers = ["bold"]
+
+[theme256.file_type.symlink_broken]
+bg = "235" # #262626
+fg = "160" # #d70000
+
+[theme256.help]
+fg = "144" # #afaf87 - olive sage
+
+[theme256.help.header]
+bg = "144" # #afaf87
+fg = "235" # #262626
+
+[theme256.help.actions]
+fg = "253" # #dadada
+modifiers = ["bold"]
+
+[theme256.help.shortcuts]
+fg = "253" # #dadada
+
+[theme256.notice.filter]
+bg = "73" # #5fafaf - teal (approx #33A999)
+fg = "235" # #262626
+
+[theme256.notice.progress]
+bg = "30" # #008787 - dark teal
+fg = "73" # #5fafaf - teal
+
+[theme256.prompt.cursor]
+bg = "30" # #008787
+fg = "253" # #dadada
+
+[theme256.prompt.delete]
+bg = "130" # #af5f00 - rust
+fg = "235" # #262626
+
+[theme256.prompt.input]
+bg = "236" # #303030
+fg = "253" # #dadada
+
+[theme256.prompt.label]
+bg = "73" # #5fafaf - teal
+fg = "235" # #262626
+
+[theme256.prompt.selected]
+bg = "37" # #00afaf - cyan (approx #2AA198)
+fg = "253" # #dadada
+
+[theme256.scrollbar]
+show_ends = false
+
+[theme256.scrollbar.ends]
+bg = "100" # #878700 - darker olive (approx #7c7755)
+fg = "236" # #303030
+
+[theme256.scrollbar.thumb]
+bg = "236" # #303030
+fg = "144" # #afaf87
+
+[theme256.scrollbar.track]
+fg = "100" # #878700
+
+[theme256.status.detail]
+bg = "37" # #00afaf - cyan (approx #2AA198)
+fg = "235" # #262626
+
+[theme256.status.label]
+bg = "30" # #008787 - dark teal
+fg = "253" # #dadada
+
+[theme256.table.body]
+bg = "237" # #3a3a3a
+fg = "253" # #dadada
+
+[theme256.table.delete]
+bg = "136" # #af8700 - amber
+fg = "235" # #262626
+
+[theme256.table.header]
+bg = "100" # #878700 - darker olive (approx #7c7755)
+fg = "235" # #262626
+
+[theme256.table.header_sorted]
+bg = "144" # #afaf87 - olive sage
+fg = "235" # #262626
+modifiers = ["bold"]
+
+[theme256.table.marked]
+bg = "37" # #00afaf - cyan (approx #2AA198)
+fg = "253" # #dadada
+
+[theme256.table.selected]
+bg = "30" # #008787 - dark teal
+fg = "253" # #dadada