Load config from default location on app startup

Previously, when no --config flag was provided, the app would use
Config::default() which ignores any saved user preferences in
~/.config/fresh/config.json.

Now it uses Config::load_or_default() which tries to load from the
default config location first, falling back to defaults only if the
file doesn't exist or fails to parse.

This fixes the issue where theme selection (and other config changes)
weren't persisted across app restarts.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: sinelaw

src/config.rs

@@ -382,6 +382,30 @@ impl Default for MenuConfig {
 }
 
 impl Config {
+    /// Get the default config file path
+    pub fn default_config_path() -> Option<std::path::PathBuf> {
+        dirs::config_dir().map(|d| d.join("fresh").join("config.json"))
+    }
+
+    /// Load configuration from the default location, falling back to defaults if not found
+    pub fn load_or_default() -> Self {
+        if let Some(config_path) = Self::default_config_path() {
+            if config_path.exists() {
+                match Self::load_from_file(&config_path) {
+                    Ok(config) => return config,
+                    Err(e) => {
+                        tracing::warn!(
+                            "Failed to load config from {}: {}, using defaults",
+                            config_path.display(),
+                            e
+                        );
+                    }
+                }
+            }
+        }
+        Self::default()
+    }
+
     /// Load configuration from a JSON file
     pub fn load_from_file<P: AsRef<Path>>(path: P) -> Result<Self, ConfigError> {
         let contents = std::fs::read_to_string(path.as_ref())

src/main.rs

@@ -127,7 +127,8 @@ fn main() -> io::Result<()> {
             }
         }
     } else {
-        config::Config::default()
+        // Try to load from default location, fall back to defaults
+        config::Config::load_or_default()
     };
 
     // Set up terminal first