Adopt Semifold CI and prepare 0.2.0-alpha pre-release (#62)

Refer: http://semifold.noctisynth.org/

## Summary by Sourcery

Adopt Semifold-based release management and prepare the project for a
0.2.0-alpha pre-release across Rust and UI packages.

New Features:
- Introduce Semifold CI release workflow to orchestrate builds,
publishing, and changelog management.
- Add Semifold status workflow to report release status on pull
requests.
- Add workspace-level Node tooling and scripts to manage Tauri version
bumping and project preparation.

Enhancements:
- Refactor GitHub Actions workflows for build, test, check, and lint to
simplify pnpm usage, update action versions, and standardize artifact
paths.
- Move Rust profile configuration into a new Cargo workspace and add a
pnpm workspace for the UI package.
- Configure Semifold changelog and release metadata for Rust and Node
packages, including alpha pre-release tagging.

Build:
- Replace the tag-triggered GitHub release workflow with a branch-based
Semifold CI pipeline that builds artifacts for Linux, macOS, and Windows
and uploads them for publishing.
- Update CI action versions (checkout, setup-node, upload-artifact,
download-artifact) and adjust Rust cache configuration and artifact
locations.
- Add root workspace package.json, pnpm-workspace.yaml, and pnpm
overrides to centralize tooling and dependency management.

CI:
- Add a dedicated Semifold status GitHub Actions workflow for pull
requests to main.
- Update existing check, lint, test, and build workflows to align with
the new workspace layout and artifact directories.

Deployment:
- Integrate Semifold configuration for automated publishing to crates.io
and npm, including pre-checks, post-version hooks, and use of stored
build artifacts in releases.

Tests:
- Adjust test workflow artifact paths to match the new target directory
structure and workspace configuration.

Chores:
- Remove unused Python packaging files and old Node lockfiles that are
no longer part of the build or release process.

1 files changed, 9 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..1a8ac7a
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,9 @@
+[workspace]
+members = ["src-tauri"]
+resolver = "3"
+
+[profile.dev]
+opt-level = 0
+
+[profile.release]
+opt-level = 3