chore: Create stable35 branch and target Nextcloud 36 on main #24

Context

Dependabot PR #20 proposes upgrading PHPUnit from 10.5.63 to 13.3.2:

#20

This update exposed a compatibility problem. The application currently declares support for Nextcloud 32 through 35 in appinfo/info.xml, while newer development dependencies may require PHP versions that are not supported by all those Nextcloud releases.

Since the application has not been published in the Nextcloud App Store and Nextcloud 32–34 are no longer part of our planned maintenance scope, we can simplify version management without creating unnecessary stable branches.

Goal

Separate the Nextcloud 35 maintenance line from Nextcloud 36 development.

This will:

• Preserve a dedicated branch for Nextcloud 35.
• Allow main to target Nextcloud 36 without changing the compatibility declared for Nextcloud 35.
• Establish a clear boundary for future dependency updates and maintenance.
• Avoid declaring compatibility with older Nextcloud versions that we do not intend to maintain.

Implementation

1. Create stable35 from the current main, before modifying its compatibility requirements.

2. Update appinfo/info.xml on stable35:

   <nextcloud min-version="35" max-version="35"/>

3. Update appinfo/info.xml on main:

   <nextcloud min-version="36" max-version="36"/>

4. Validate both XML files and verify the resulting branch contents.

Acceptance criteria

• stable35 exists and preserves the code from main before its compatibility change.
• stable35 declares support exclusively for Nextcloud 35.
• main declares support exclusively for Nextcloud 36.
• Both info.xml files pass XML validation.
• No unrelated application functionality or dependencies are modified.
• All changes use signed commits with DCO.

Relationship with PR #20

This change establishes separate maintenance targets but does not, by itself, make PHPUnit 13 compatible with the supported PHP versions.

PR #20 must be evaluated separately against the PHP requirements of Nextcloud 36. Its merge is not part of this issue.

Out of scope

• Creating stable32, stable33, or stable34.
• Updating PHPUnit, Composer, or PHP requirements.
• Changing CI workflows.
• Publishing releases or Git tags.