Mintd lib (#914)

* feat(cdk-integration-tests): refactor regtest setup and mintd integration

- Replace shell-based regtest setup with Rust binary (start_regtest_mints)
- Add cdk-mintd crate to workspace and integration tests
- Improve environment variable handling for test configurations
- Update integration tests to use proper temp directory management
- Remove deprecated start_regtest.rs binary
- Enhance CLN client connection with retry logic
- Simplify regtest shell script (itests.sh) to use new binary
- Fix tracing filters and improve error handling in setup
- Update dependencies and configurations for integration tests

fix: killing

chore: comment tests for ci debugging

chore: compile

Revert "chore: comment tests for ci debugging"

This reverts commit bfc594c11cf37caeaa6445cb854ae5567d2da6bd.

* chore: sql cipher

* fix: removal of sqlite cipher

* fix: auth password

* refactor(cdk-mintd): improve database password handling and function signatures

- Pass database password as parameter instead of parsing CLI args in setup_database
- Update function signatures for run_mintd and run_mintd_with_shutdown to accept db_password
- Remove direct CLI parsing from database setup logic
- Fix auth database initialization to use correct type when sqlcipher feature enabled

misc/interactive_regtest_mprocs.sh

@@ -123,7 +123,7 @@ cargo build -p cdk-integration-tests --bin start_regtest
 cargo build --bin cdk-mintd
 
 echo "Starting regtest network (Bitcoin + Lightning nodes)..."
-cargo run --bin start_regtest &
+cargo run --bin start_regtest -- --enable-logging "$CDK_ITESTS_DIR" &
 export CDK_REGTEST_PID=$!
 
 # Create named pipe for progress tracking