feat(config): add config module with multi-profile TOML deserialization

- Config, Profile and RepoEntry structs with serde::Deserialize
- RepoEntry::clone_url() builds authenticated URL per provider
  (github, gitlab, bitbucket)
- RepoEntry::cache_path() returns ~/.cache/git-reports/{profile}/{provider}/{owner}/{name}
- load_config() reads and parses config.toml

Author: madkoding

src/config.rs

@@ -0,0 +1,69 @@
+use serde::Deserialize;
+use std::fs;
+use std::path::Path;
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct Config {
+    pub profile: Vec<Profile>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct Profile {
+    pub name: String,
+    pub email: String,
+    pub token: String,
+    #[serde(default)]
+    pub repo: Vec<RepoEntry>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct RepoEntry {
+    pub provider: String, // github | gitlab | bitbucket
+    pub owner: String,
+    pub name: String,
+}
+
+impl RepoEntry {
+    /// Construye la URL de clone con el token embebido según el provider.
+    pub fn clone_url(&self, token: &str) -> String {
+        match self.provider.as_str() {
+            "github" => format!(
+                "https://{}@github.com/{}/{}.git",
+                token, self.owner, self.name
+            ),
+            "gitlab" => format!(
+                "https://oauth2:{}@gitlab.com/{}/{}.git",
+                token, self.owner, self.name
+            ),
+            "bitbucket" => format!(
+                "https://x-token-auth:{}@bitbucket.org/{}/{}.git",
+                token, self.owner, self.name
+            ),
+            other => format!(
+                "https://{}@{}/{}/{}.git",
+                token, other, self.owner, self.name
+            ),
+        }
+    }
+
+    /// Devuelve la ruta de caché local para este repo.
+    /// ~/.cache/git-reports/{profile_name}/{provider}/{owner}/{name}
+    pub fn cache_path(&self, profile_name: &str) -> std::path::PathBuf {
+        let base = dirs_next::cache_dir()
+            .unwrap_or_else(|| std::path::PathBuf::from("/tmp"))
+            .join("git-reports")
+            .join(profile_name)
+            .join(&self.provider)
+            .join(&self.owner)
+            .join(&self.name);
+        base
+    }
+}
+
+/// Carga y deserializa el archivo config.toml desde la ruta indicada.
+pub fn load_config(path: &str) -> Result<Config, String> {
+    let content = fs::read_to_string(Path::new(path))
+        .map_err(|e| format!("No se pudo leer '{}': {}", path, e))?;
+    toml::from_str::<Config>(&content)
+        .map_err(|e| format!("Error al parsear '{}': {}", path, e))
+}