8367531: Template Framework: use scopes and tokens instead of misbehaving immediate-return-queries

[rm-gh-8]

Backporting JDK-8367531: Template Framework: use scopes and tokens instead of misbehaving immediate-return-queries.

This PR fixes an execution-order bug where immediate-return queries (like sample(), count()) would "float" above deferred tokens (like addDataName), producing confusing and incorrect results. The fix converts all state-querying operations to token-based APIs with lambda callbacks, and introduces explicit ScopeToken types with configurable transparency.

For parity with Oracle JDK.

It is part of a series of dependent PRs for JDK 25, related to the following list of ordered issues:

8358772: Template-Framework Library: Primitive Types
8358600: Template-Framework Library: Template for TestFramework test class
8359412: Template-Framework Library: Operations and Expressions
8367531: Template Framework: use scopes and tokens instead of misbehaving immediate-return-queries
8370489: Some compiler tests miss the @key randomness

Ran related tests on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

make test TEST=test/hotspot/jtreg/testlibrary_tests/template_framework

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8367531 needs maintainer approval

Integration blocker

 ⚠️ Dependency #386 must be integrated first

Issue

• JDK-8367531: Template Framework: use scopes and tokens instead of misbehaving immediate-return-queries (Enhancement - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/388/head:pull/388
$ git checkout pull/388

Update a local copy of the PR:
$ git checkout pull/388
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/388/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 388

View PR using the GUI difftool:
$ git pr show -t 388

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/388.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back rm-gh-8! A progress list of the required criteria for merging this PR into pr/386 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 00: Full (35df999e)

[rm-gh-8]

Review will be requested after merging from head once the prerequisite is pushed. The merge from head will require a re-review.