Add non-custom app packaging automation #15

	###
	# SPDX-License-Identifier: AGPL-3.0
	#
	# Author: Bernd rederlechner <[email protected]
	#
	# Assemble a customisation for recent trunk or a stable branch
	# If trunk, no backports are considered. For stable, only the
	# backports targetted for this baseline are considered.
	#
	# Assembly fails if a PR does not merge automatically.
	#

	name: MCLOUD custom server build

	on:
	workflow_call:
	inputs:
	stable:
	description: name of the stable baseline branch to build on
	required: true
	type: string
	stable:
	description: increment to the nextcloud release name
	required: true
	type: number
	output:
	tag: ${{ steps.tag_name.result }}

	jobs:
	build-custom:
	runs-on: ubuntu-latest
	env:
	BUILD_TOKEN: ${{ secrets.BUILD_TOKEN \|\| secrets.GITHUB_TOKEN }}
	steps:
	- name: Compute release tag name
	id: tag_name
	run: \|
	echo "result="nmc${INPUTS_STABLE##*/}-$INPUTS_INCREMENT" >> $GITHUB_OUTPUT

	- name: Check ambigouity
	id: release_not_exist
	uses: actions/github-script@v6
	with:
	github-token: ${{ env.BUILD_TOKEN }}
	script: \|
	// Test whether release is readable
	try {
	const releaseTag = "${{ steps.tag_name.result }}";
	const { data: release } = await github.rest.repos.getReleaseByTag({
	owner: context.repo.owner,
	repo: context.repo.repo,
	tag: releaseTag
	});
	core.setFailed(`Release tags/${releaseTag} already exists!`);
	} catch (error) {
	// expect release to be not found
	}

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