fix: Implement proper GoCardless authentication and add dev features

Authentication Fixes:
- Implement proper async GoCardless token management in leggend service
- Add automatic token refresh and creation for expired/missing tokens
- Unify auth.json storage path between CLI and API (~/.config/leggen/)
- Fix 401 Unauthorized errors when accessing GoCardless API

Development Enhancements:
- Add --reload flag to leggend for automatic file watching and restart
- Add --host and --port options for flexible service binding
- Include both leggend/ and leggen/ directories in reload watching
- Improve development workflow with hot reloading

Configuration Consistency:
- Standardize config path to ~/.config/leggen/config.toml for both CLI and API
- Ensure auth.json is stored in same location as main config
- Add httpx dependency for async HTTP requests in leggend service

Verified working: leggen status command successfully authenticates
and retrieves bank/account data via leggend API service.

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

Co-Authored-By: Claude <noreply@anthropic.com>

pyproject.toml

@@ -3,7 +3,7 @@ name = "leggen"
 version = "0.6.11"
 description = "An Open Banking CLI"
 authors = [{ name = "Elisiário Couto", email = "elisiario@couto.io" }]
-requires-python = "=3.12.0"
+requires-python = "~=3.12.0"
 readme = "README.md"
 license = "MIT"
 keywords = [
@@ -35,6 +35,7 @@ dependencies = [
     "uvicorn[standard]>=0.24.0,<1",
     "apscheduler>=3.10.0,<4",
     "tomli-w>=1.0.0,<2",
+    "httpx>=0.28.1",
 ]
 
 [project.urls]
@@ -51,10 +52,10 @@ dev = [
 ]
 
 [tool.hatch.build.targets.sdist]
-include = ["leggen"]
+include = ["leggen", "leggend"]
 
 [tool.hatch.build.targets.wheel]
-include = ["leggen"]
+include = ["leggen", "leggend"]
 
 [build-system]
 requires = ["hatchling"]