feat(projectconfig): add RPM repo resources and repo-set templates

[reubeno]

Introduce a [resources] section that lets projects declare RPM repos and reusable layout templates in TOML, replacing per-consumer URL hard-coding. Distro versions select inputs per use-case (rpm-build vs image-build), with sets expanded lazily during validation.

Ship two built-in templates: azl-standard (base/sdk x main/debuginfo/srpms) and koji-dist-repo (per-arch trees + src). Adds reference + explanation docs with an end-to-end TOML example, regenerates the JSON schema, and rejects local gpg-key paths for rpm-build (mock evaluates URIs inside the chroot).

NOTE: This does not wire up any consumers of the new data; this is primarily focused on the schema extension and being able to process the new data.

[Copilot]

Pull request overview

Adds a new [resources] configuration section to centralize RPM repository definitions and reusable “repo set template” layouts, then lets distro versions select per-use-case repo inputs (rpm-build vs image-build). This moves repo URL/layout knowledge out of individual consumers (mock templates / kiwi configs) and into projectconfig + schema/docs.

Changes:

• Introduce ResourcesConfig with RPM repos, repo-set templates, and repo-set instantiations (including expansion and validation).
• Add inputs to DistroVersionDefinition to reference repos / repo sets per build use-case, with validation (including rejecting local gpg-key for rpm-build).
• Regenerate JSON schema + scenario snapshots, and add user documentation plus default built-in templates.

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
schemas/azldev.schema.json	Schema update for [resources] and distros.*.versions.*.inputs.
scenario/__snapshots__/TestSnapshotsContainer_config_generate-schema_stdout_1.snap	Snapshot update for schema generation output.
scenario/__snapshots__/TestSnapshots_config_generate-schema_stdout_1.snap	Snapshot update for schema generation output.
internal/projectconfig/resources.go	New resources model, repo-set expansion logic, and repo/GPG/URI validation helpers.
internal/projectconfig/resources_internal_test.go	Unit tests for resources validation and expansion helpers.
internal/projectconfig/project.go	Wire resources + distro input validation into ProjectConfig.Validate().
internal/projectconfig/loader.go	Merge [resources] across config files with per-file relative-path resolution.
internal/projectconfig/distro.go	Add DistroVersionDefinition.Inputs + DistroVersionInputs types.
internal/projectconfig/configfile.go	Allow config files to declare [resources] (schema + load structure).
docs/user/reference/config/resources.md	Reference documentation for the new [resources] section.
docs/user/reference/config/distros.md	Document distros.*.versions.*.inputs.
docs/user/reference/config/config-file.md	Add resources to root config layout.
docs/user/README.md	Link new explanation/reference docs.
docs/user/explanation/repos.md	Explanation doc for repo resources, templates, and sets.
defaultconfigs/content/defaults.toml	Ship built-in templates (azl-standard, koji-dist-repo).

Comments suppressed due to low confidence (1)

internal/projectconfig/project.go:175

• Same wrapping style issue as above: this %w wrap would be clearer with the repo’s standard "context:\n%w" formatting to keep nested errors readable.

			imageBuild, err := version.EffectiveImageBuildRepos(resources)
			if err != nil {
				return fmt.Errorf("distro %q version %q: %w", distroName, versionName, err)
			}

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (2)

internal/projectconfig/resources.go:763

• The undefined-template error suggests defining the template under [resources.rpm-repo-set-templates.%s], but template names are allowed to include '.'/':' etc (per the name regex) which would require quoting in TOML keys. Consider rewording to avoid implying an unquoted table header (e.g., “define a key under [resources.rpm-repo-set-templates] named …”), or render the example using a quoted key form.

		return nil, fmt.Errorf(
			"rpm-repo-set %#q references undefined `template` %#q; "+
				"define it under [resources.rpm-repo-set-templates.%s]",
			setName, set.Template, set.Template,
		)

internal/projectconfig/resources.go:1090

• This error message formats repo/set values with %q. Elsewhere in this file errors tend to use %#q for strings (and the repo has a convention for that), which makes messages unambiguous when values contain escapes. Consider switching these to %#q for consistency/readability.

		return fmt.Errorf(
			"`inputs.%s` entry %d sets both `repo` (%q) and `set` (%q); exactly one is required",
			useCase, index, entry.Repo, entry.Set,
		)

[reubeno]

Addressed the latest Copilot findings in d29d4a8:

• resources.go:763 / 727 / 1087 (TOML key examples): rephrased the undefined-template and collision error messages to reference the parent table ([resources.rpm-repo-set-templates] / [resources.rpm-repos]) rather than synthesizing a child table header that may need quoting.
• resources.go:1090 (%q → %#q): switched the XOR error in validateDistroVersionInput to use %#q for repo/set values to match the rest of the file.
• resources.go:685 (EffectiveRpmRepos doc): clarified that path absolutization is a precondition handled by WithAbsolutePaths during load/merge — the method itself only joins URIs and validates.

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 4 comments.

Comments suppressed due to low confidence (1)

internal/projectconfig/resources.go:985

• Template sub-repo subpath validation rejects leading slashes but does not reject .. path segments, even though joinSetBaseURI rejects .. during set expansion. This means an invalid template can pass validation and only fail later during expansion (with less direct context). Consider rejecting .. segments here as well to keep template validation self-contained and consistent.

		if strings.HasPrefix(sub.Subpath, "/") {
			return fmt.Errorf(
				"rpm-repo-set-template %#q sub-repo %#q `subpath` must be relative (no leading slash)",
				name, sub.Name,
			)

[Tonisal-byte]

Looks good :)

[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 1 comment.