This commit introduces a TDD testing framework for the `collect` commands and resolves a build failure.
- A `TDD/` directory has been added to house tests for the `collect` commands.
- An environment variable `BORG_PLEXSUS=0` has been implemented to enable a mock mode, which prevents external network calls during testing.
- The `collect` commands have been updated to use the command's output streams, allowing for output capturing in tests.
- A `pkg/mocks` package has been added to provide mock implementations for testing.
- The `.gitignore` file has been updated to exclude generated `.datanode` files.
- The "flag redefined" build error has been fixed by refactoring the root command initialization in `cmd/root.go` to prevent duplicate flag definitions.
This commit introduces a new `DataNode` package, which provides an in-memory, `fs.FS`-compatible filesystem with a `debme`-like interface. The `DataNode` can be serialized to and from a TAR archive, making it suitable for storing downloaded assets.
The `pwa` and `serve` commands have been refactored to use the `DataNode`. The `pwa` command now packages downloaded PWA assets into a `DataNode` and saves it as a `.dat` file. The `serve` command loads a `.dat` file into a `DataNode` and serves its contents.
