feat(package): Support PHP composer dev-* branch

[douyun-dtyq]

Users can POST to /packages/{owner}/composer/{vendor}/{project}/-/composer/dev-branch to create a dev-<branchname> version as a virtual version to link to branch (or other refs) archive zips. The behavior matches Packagist.

Also set composer SemverCompatible to false to support this.

Needs a migration like UPDATE package SET semver_compatible = false WHERE "type" = 'composer'; for the SemverCompatible change. But I'm not sure how to create a migration commit for this project, so it's currently missing. Guidance on this would be appreciated!

Code was written by GitHub Copilot with GPT5.5, but all changes have been thoroughly reviewed and tested by myself (both newly added unit tests and on a real instance). I take full responsibility for the code.

Discussions:

1. SemverCompatible seems not very useful for the package model and is often just a cumbersome burden. In my opinion, trying to parse the version string and silently failing is better than static SemverCompatible control for packages.
2. For dev-* versions: should we allow out-of-scope repositories (like the package is at someorg, but the dev-master links to the master branch of anotherorg/somerepo) or even external links?
3. The API path is not exposed to Swagger (due to it being at /packages, not /v1/packages) and WebUI (since current composer package workflow is API only). Maybe we can add a simple switch on the WebUI for this feature?
4. Property, struct, API path, and helper naming or placement may not fully match the project conventions. Feel free to suggest any changes.

BTW: should we alias/link/mount /packages routes to /v1/packages to show it in swagger?