RFR: 8359936: StableValues can release the underlying function after complete computation

[Per Minborg]

This PR proposes to release the underlying function if a stable function or collection has invoked its underlying supplier exhaustively so that it can be collected.

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Commit messages:
 - Clean up
 - Fix bug
 - Simplify
 - Revert to records
 - Make code more like the old one
 - Add removable underlying functions

Changes: https://git.openjdk.org/jdk/pull/25878/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25878&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8359936
  Stats: 294 lines in 14 files changed: 238 ins; 9 del; 47 mod
  Patch: https://git.openjdk.org/jdk/pull/25878.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25878/head:pull/25878

PR: https://git.openjdk.org/jdk/pull/25878