fix: stamp release version from tag

[pandego]

Summary

• stamp the release tag version into Cargo.toml before desktop, CLI, and Docker release builds
• sync crates/openfang-desktop/tauri.conf.json to the same tag version for desktop releases

Problem

The v0.5.5 release artifacts can report stale versions because the repo metadata checked out by the release workflow still declares older values:

• workspace Cargo version stayed at 0.5.1
• desktop Tauri config stayed at 0.1.0

That lets packaged binaries drift from the actual release tag.

Fix

For tag-triggered release jobs, derive the version from github.ref_name, strip the leading v, and stamp it into the workspace Cargo metadata before building.

For the desktop release job, also update the Tauri config version before packaging.

Validation

• replayed the stamping logic locally against v0.5.5
• confirmed it rewrites both the Cargo workspace version and desktop Tauri version to 0.5.5

Closes #884

[jaberjaber23]

Reviewed. Good intent but the ~20-line Node.js inline script is copy-pasted 3 times across 3 jobs. Extract into a shared script file. Also the Cargo.toml regex is fragile and there is no Cargo.lock regeneration after modifying Cargo.toml.