feat: added providers management settings with ability to add or remove providers (#76)

* feat: implement adding opencode providers in openchamber settings

* feat: implement provider authentication management with removal functionality

packages/desktop/src-tauri/src/opencode_auth.rs

@@ -0,0 +1,116 @@
+use anyhow::{anyhow, Result};
+use log::info;
+use serde_json::Value;
+use std::path::PathBuf;
+use tokio::fs;
+
+/// Get OpenCode data directory path (~/.local/share/opencode)
+fn get_data_dir() -> PathBuf {
+    dirs::home_dir()
+        .expect("Cannot determine home directory")
+        .join(".local")
+        .join("share")
+        .join("opencode")
+}
+
+/// Get auth file path
+fn get_auth_file() -> PathBuf {
+    get_data_dir().join("auth.json")
+}
+
+/// Ensure data directory exists
+async fn ensure_data_dir() -> Result<()> {
+    let data_dir = get_data_dir();
+    fs::create_dir_all(&data_dir).await?;
+    Ok(())
+}
+
+/// Read auth.json file
+pub async fn read_auth() -> Result<Value> {
+    let auth_file = get_auth_file();
+
+    if !auth_file.exists() {
+        return Ok(Value::Object(serde_json::Map::new()));
+    }
+
+    let content = fs::read_to_string(&auth_file).await?;
+    let trimmed = content.trim();
+
+    if trimmed.is_empty() {
+        return Ok(Value::Object(serde_json::Map::new()));
+    }
+
+    serde_json::from_str(trimmed).map_err(|e| anyhow!("Failed to parse auth file: {}", e))
+}
+
+/// Write auth.json file with backup
+pub async fn write_auth(auth: &Value) -> Result<()> {
+    ensure_data_dir().await?;
+
+    let auth_file = get_auth_file();
+
+    // Create backup before writing
+    if auth_file.exists() {
+        let file_name = auth_file
+            .file_name()
+            .and_then(|name| name.to_str())
+            .ok_or_else(|| anyhow!("Invalid auth file name"))?;
+
+        let backup_path = auth_file.with_file_name(format!("{file_name}.openchamber.backup"));
+        fs::copy(&auth_file, &backup_path).await?;
+        info!("Created auth backup: {}", backup_path.display());
+    }
+
+    let json_string = serde_json::to_string_pretty(auth)?;
+    fs::write(&auth_file, json_string).await?;
+    info!("Successfully wrote auth file");
+
+    Ok(())
+}
+
+/// Remove provider auth entry from auth.json
+pub async fn remove_provider_auth(provider_id: &str) -> Result<bool> {
+    if provider_id.is_empty() {
+        return Err(anyhow!("Provider ID is required"));
+    }
+
+    let mut auth = read_auth().await?;
+
+    let auth_obj = auth
+        .as_object_mut()
+        .ok_or_else(|| anyhow!("Auth file is not a valid JSON object"))?;
+
+    if !auth_obj.contains_key(provider_id) {
+        info!(
+            "Provider {} not found in auth file, nothing to remove",
+            provider_id
+        );
+        return Ok(false);
+    }
+
+    auth_obj.remove(provider_id);
+    write_auth(&auth).await?;
+    info!("Removed provider auth: {}", provider_id);
+
+    Ok(true)
+}
+
+/// Get provider auth entry
+pub async fn get_provider_auth(provider_id: &str) -> Result<Option<Value>> {
+    let auth = read_auth().await?;
+
+    Ok(auth
+        .as_object()
+        .and_then(|obj| obj.get(provider_id))
+        .cloned())
+}
+
+/// List all provider IDs with auth
+pub async fn list_provider_auths() -> Result<Vec<String>> {
+    let auth = read_auth().await?;
+
+    Ok(auth
+        .as_object()
+        .map(|obj| obj.keys().cloned().collect())
+        .unwrap_or_default())
+}