Extract config/profile management to library crate (#410)

* docs: rewrite README for presentation readiness

- Add hero section with clear value proposition
- Create 'Why redisctl?' section explaining benefits over raw APIs
- Add feature showcase with before/after examples
- Include 4 real-world usage scenarios
- Move installation section lower after establishing value
- Streamline quick start to 3 simple steps
- Maintain all technical accuracy while improving readability

* docs: remove emojis from README

* feat: extract config/profile management to redisctl-config library

Closes #409

- Created new redisctl-config library crate for reusable config system
- Moved config.rs and credential_store.rs to new crate
- Refactored to use thiserror for library errors
- Added clap::ValueEnum derive to DeploymentType
- Updated all imports in redisctl to use new library
- Removed old config and credential_store modules from redisctl
- All tests passing, clippy clean

Benefits:
- Config system can now be reused by other tools (e.g., redis-up)
- Cleaner separation of concerns
- Independent versioning for config library
- Well-documented public API

Breaking changes: None (internal refactoring only)

Author: joshrotenberg

Cargo.lock

@@ -1,11 +1,13 @@
 [workspace]
 resolver = "2"
 members = [
+    "crates/redisctl-config",
     "crates/redis-cloud",
     "crates/redis-enterprise",
     "crates/redisctl",
 ]
 default-members = [
+    "crates/redisctl-config",
     "crates/redis-cloud",
     "crates/redis-enterprise",
     "crates/redisctl",
@@ -91,6 +93,7 @@ serial_test = "3.1"
 pretty_assertions = "1.4"
 
 # Internal crates
+redisctl-config = { path = "crates/redisctl-config" }
 redis-cloud = { path = "crates/redis-cloud" }
 redis-enterprise = { path = "crates/redis-enterprise" }
 

Cargo.toml

@@ -0,0 +1,41 @@
+[package]
+name = "redisctl-config"
+version = "0.1.0"
+edition = "2024"
+authors = ["Josh Rotenberg <[email protected]>"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/joshrotenberg/redisctl"
+homepage = "https://github.com/joshrotenberg/redisctl"
+description = "Configuration and profile management for Redis CLI tools"
+keywords = ["redis", "config", "profile", "credentials"]
+categories = ["config", "authentication"]
+readme = "README.md"
+
+[dependencies]
+# Serialization
+serde = { version = "1.0", features = ["derive"] }
+toml = "0.8"
+
+# Error handling (use thiserror for libraries)
+thiserror = "2.0"
+
+# Platform paths
+directories = "6.0"
+
+# Environment variable expansion
+shellexpand = "3.1"
+
+# CLI support (for ValueEnum derive)
+clap = { version = "4.5", features = ["derive"] }
+
+# Optional: Secure credential storage
+keyring = { version = "3.6", optional = true, features = ["apple-native", "windows-native", "linux-native"] }
+
+[dev-dependencies]
+serial_test = "3.1"
+tempfile = "3.8"
+
+[features]
+default = []
+# Note: secure-storage may not work on musl targets due to keyring native dependencies
+secure-storage = ["dep:keyring"]

crates/redisctl-config/Cargo.toml

@@ -0,0 +1,107 @@
+# redisctl-config
+
+Configuration and profile management for Redis CLI tools.
+
+## Overview
+
+This library provides a reusable configuration and profile system for managing
+credentials and settings for Redis Cloud and Redis Enterprise deployments.
+
+## Features
+
+- Multiple named profiles for different Redis deployments
+- Secure credential storage using OS keyring (optional)
+- Environment variable expansion in config files
+- Platform-specific config file locations
+- Support for both Redis Cloud and Redis Enterprise
+
+## Installation
+
+Add this to your `Cargo.toml`:
+
+```toml
+[dependencies]
+redisctl-config = "0.1"
+
+# Optional: Enable secure credential storage
+redisctl-config = { version = "0.1", features = ["secure-storage"] }
+```
+
+## Usage
+
+### Basic Configuration
+
+```rust
+use redisctl_config::{Config, Profile, DeploymentType, ProfileCredentials};
+
+// Load configuration from standard location
+let config = Config::load()?;
+
+// Create a new Cloud profile
+let profile = Profile {
+    deployment_type: DeploymentType::Cloud,
+    credentials: ProfileCredentials::Cloud {
+        api_key: "your-api-key".to_string(),
+        api_secret: "your-secret".to_string(),
+        api_url: "https://api.redislabs.com/v1".to_string(),
+    },
+    files_api_key: None,
+};
+
+// Add profile to config
+let mut config = Config::default();
+config.set_profile("production".to_string(), profile);
+config.save()?;
+```
+
+### Profile Resolution
+
+```rust
+// Resolve which profile to use for Cloud operations
+let profile_name = config.resolve_cloud_profile(None)?;
+let profile = config.profiles.get(&profile_name).unwrap();
+
+// Get credentials with keyring support
+if let Some((api_key, api_secret, api_url)) = profile.resolve_cloud_credentials()? {
+    println!("API URL: {}", api_url);
+}
+```
+
+### Credential Storage
+
+```rust
+use redisctl_config::CredentialStore;
+
+let store = CredentialStore::new();
+
+// Store credential in keyring (requires secure-storage feature)
+#[cfg(feature = "secure-storage")]
+let reference = store.store_credential("my-key", "secret-value")?;
+
+// Retrieve credential (with environment variable fallback)
+let value = store.get_credential("${MY_VAR}", Some("MY_VAR"))?;
+```
+
+## Environment Variables
+
+Credentials can reference environment variables in the config file:
+
+```toml
+[profiles.production]
+deployment_type = "cloud"
+api_key = "${REDIS_CLOUD_API_KEY}"
+api_secret = "${REDIS_CLOUD_SECRET_KEY}"
+api_url = "${REDIS_CLOUD_API_URL:-https://api.redislabs.com/v1}"
+```
+
+## Config File Location
+
+The config file is automatically placed in platform-specific locations:
+
+- **Linux/macOS**: `~/.config/redisctl/config.toml`
+- **macOS** (fallback): `~/Library/Application Support/com.redis.redisctl/config.toml`
+- **Windows**: `%APPDATA%\redis\redisctl\config.toml`
+
+## License
+
+Licensed under either of Apache License, Version 2.0 or MIT license at your option.