Fix PyPI release pipeline with dynamic versioning from git tags

[Copilot]

PyPI uploads were failing with "File already exists" because the version was hardcoded to 0.1.0 while git tags like v0.3.0-alpha existed. CI would always build 0.1.0 regardless of the tag pushed.

Changes

• pyproject.toml: Replace hardcoded version with setuptools-scm for automatic version derivation from git tags

  • Added setuptools-scm>=8.0 to build dependencies
  • Set dynamic = ["version"]
  • Configured tag regex to handle -alpha, -beta, -rc suffixes

• src/meshcore_proxy/__init__.py: Replace static __version__ = "0.1.0" with dynamic import from package metadata

• .github/workflows/ci.yml: Add fetch-depth: 0 to checkout step so setuptools-scm can access git history

• README.md: Document versioning workflow and release process

Version Resolution

Scenario	Example Tag	Package Version
On tagged commit	v0.4.0-alpha	0.4.0a0
2 commits after tag	v0.4.0-alpha	0.4.0a1.dev2
No tags	-	0.0.0.dev0

Each git tag now produces a unique PyPI version matching the tag, preventing upload conflicts.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Release to PiPy isn't working</issue_title>
<issue_description>There's an issue with the release pipeline shipping to PiPY:

Run python -m twine upload dist/*
Uploading distributions to https://upload.pypi.org/legacy/
Uploading meshcore_proxy-0.1.0-py3-none-any.whl
25l
  0% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 0.0/26.1 kB • --:-- • ?
  0% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 0.0/26.1 kB • --:-- • ?
100% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 26.1/26.1 kB • 00:00 • 82.8 MB/s
100% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 26.1/26.1 kB • 00:00 • 82.8 MB/s
100% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 26.1/26.1 kB • 00:00 • 82.8 MB/s
25hWARNING  Error during upload. Retry with the --verbose option for more details. 
ERROR    HTTPError: 400 Bad Request from https://upload.pypi.org/legacy/        
         File already exists ('meshcore_proxy-0.1.0-py3-none-any.whl', with     
         blake2_256 hash                                                        
         '9db71050bd8a32301af3c3a441f93b72315ee0318ca37e89f2e19c2634feadef').   
         See https://pypi.org/help/#file-name-reuse for more information.       
Error: Process completed with exit code 1.
```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes Release to PiPy isn't working #5

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[Copilot]

Pull request overview

This PR fixes the PyPI release pipeline by replacing the hardcoded version 0.1.0 with dynamic versioning using setuptools-scm. The issue occurred because every release attempt uploaded the same version number regardless of the git tag, causing "File already exists" errors on PyPI.

Changes:

• Replaced hardcoded version with setuptools-scm for automatic version derivation from git tags
• Updated CI workflow to fetch full git history for version detection
• Added documentation for the versioning workflow and release process

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
pyproject.toml	Added setuptools-scm configuration with tag regex supporting -alpha, -beta, and -rc suffixes; set version as dynamic
src/meshcore_proxy/init.py	Replaced static version string with dynamic import from package metadata using importlib.metadata
.github/workflows/ci.yml	Added fetch-depth: 0 to build job checkout to enable setuptools-scm git tag detection
README.md	Added Development section documenting versioning workflow, release process, and version resolution examples

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[Copilot]

The new dynamic version resolution logic lacks test coverage. Since this project has comprehensive test coverage for other modules (test_cli.py and test_proxy.py), consider adding a test to verify that the version attribute is correctly set. The test should verify both the successful case (when the package is installed) and the fallback case (when PackageNotFoundError is raised).

[Copilot]

The documentation mentions tags can follow the pattern vX.Y.Z or vX.Y.Z-alpha, but the tag regex also accepts -beta and -rc[0-9]+ suffixes. The documentation should be updated to mention all supported tag formats for completeness. Consider updating line 336 to say: "Tags should follow the pattern vX.Y.Z, vX.Y.Z-alpha, vX.Y.Z-beta, or vX.Y.Z-rc<number> (e.g., v0.4.0, v0.4.0-alpha, v0.4.0-beta, v0.4.0-rc1)"

Suggested change

	**Version format:** Tags should follow the pattern `vX.Y.Z` or `vX.Y.Z-alpha` (e.g., `v0.4.0`, `v0.4.0-alpha`)
	**Version format:** Tags should follow the pattern `vX.Y.Z`, `vX.Y.Z-alpha`, `vX.Y.Z-beta`, or `vX.Y.Z-rc<number>` (e.g., `v0.4.0`, `v0.4.0-alpha`, `v0.4.0-beta`, `v0.4.0-rc1`)