Make getLoadedBuilds not to copy all coreMap builds

[dukhlov]

Related to #26596

This change refactors getLoadedBuilds() to return a BuildReferenceMapAdapter backed by the existing core map with a LoadedOnlyBuildReferenceResolver that only returns builds already loaded into memory, without triggering disk loads. This avoids the unnecessary copy and allocation.

As part of this refactoring:

• Extracted BuildReferenceResolver interface from the inner Resolver interface in BuildReferenceMapAdapter, separating build reference resolution logic from build metadata (BuildTypeDescriptor)
• Introduced LoadedOnlyBuildReferenceResolver — resolves only in-memory references, used by getLoadedBuilds()
• Introduced DefaultBuildReferenceResolver — resolves references with disk loading fallback, used by all other operations

Testing done

Manual testing done on local environment, Jenkins PR automated testing done

Screenshots (UI changes only)

Before

After

Proposed changelog entries

• Avoid unnecessary copy of all loaded builds in AbstractLazyLoadRunMap.getLoadedBuilds().

Proposed changelog category

/label internal

Proposed upgrade guidelines

N/A

Submitter checklist

• The issue, if it exists, is well-described.
• The changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developers, depending on the change) and are in the imperative mood (see examples). Fill in the Proposed upgrade guidelines section only if there are breaking changes or changes that may require extra steps from users during upgrade.
• There is automated testing or an explanation as to why this change has no tests.
• New public classes, fields, and methods are annotated with @Restricted or have @since TODO Javadocs, as appropriate.
• New deprecations are annotated with @Deprecated(since = "TODO") or @Deprecated(forRemoval = true, since = "TODO"), if applicable.
• UI changes do not introduce regressions when enforcing the current default rules of Content Security Policy Plugin. In particular, new or substantially changed JavaScript is not defined inline and does not call eval to ease future introduction of Content Security Policy (CSP) directives (see documentation).
• For dependency updates, there are links to external changelogs and, if possible, full differentials.
• For new APIs and extension points, there is a link to at least one consumer.

Desired reviewers

@jglick @timja @bennettzhu1

Before the changes are marked as ready-for-merge:

Maintainer checklist

• There are at least two (2) approvals for the pull request and no outstanding requests for change.
• Conversations in the pull request are over, or it is explicit that a reviewer is not blocking the change.
• Changelog entries in the pull request title and/or Proposed changelog entries are accurate, human-readable, and in the imperative mood.
• Proper changelog labels are set so that the changelog can be generated automatically.
• If the change needs additional upgrade steps from users, the upgrade-guide-needed label is set and there is a Proposed upgrade guidelines section in the pull request title (see example).
• If it would make sense to backport the change to LTS, be a Bug or Improvement, and either the issue or pull request must be labeled as lts-candidate to be considered.

[timja]

fyi spotbugs failure

[timja]

LGTM

[bennettzhu1]

Very nice!

[MarkEWaite]

This PR is now ready for merge. We will merge it after approximately 24 hours if there is no negative feedback. Please see the merge process documentation for more information about the merge process.

/label ready-for-merge

[github-actions]

Please take a moment and address the merge conflicts of your pull request. Thanks!