RFR: 8346552: C2: Add IR tests to check that Parse Predicate cloning in Loop Unswitching works as expected

[Manuel Hässig]

# Issue Summary

When a loop is unswitched, all parse predicates from the original loop must be cloned to the second loop that is created. Forgetting to clone a parse predicate is a common error during development on loop unswitching code that we could not catch previously. Since we have the IR-framework now, this PR introduces a test to catch this error.

# Changes

The main contribution of this PR is a test to ensure that all predicates have been cloned into an unswitched loop. This also required some relating changes:
 - add `OPAQUE_TEMPLATE_ASSERTION_PREDICATE_NODE` to the IR-framework,
 - add some missing parse predicate nodes to the IR-framework,
 - change the output of the labels of parse predicate nodes in the ideal graph so they can be recognized reliably by the IR-framework (the main problem was that `Loop ` is a prefix of `Loop Limit Check` that is hard to distinguish with spaces instead of underlines),
 - rework the regex for detecting parse predicates in the IR-framework,
 - add a test to ensure parse predicates are cloned into unswitched loops.

# Testing

- [Github Actions](https://github.com/mhaessig/jdk/actions/runs/14266369099)
- tier1 through tier3 plus Oracle internal testing

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Commit messages:
 - Add IR test for predicate cloning
 - ir-framework: make the parse predicate node regex more robust
 - ir-framework: add auto vectorization check node
 - ir-framework: add opaque template assertion predicate node

Changes: https://git.openjdk.org/jdk/pull/24479/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24479&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8346552
  Stats: 131 lines in 3 files changed: 126 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/24479.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24479/head:pull/24479

PR: https://git.openjdk.org/jdk/pull/24479