RFR: 6004: Should add tenuring summary to the GC visualization

[Aymane Harmaz]

This change adds a new tab to display the tenuring distribution for GC cycles.

There are 3 case scenarios:
- Single GC cycle selected: A histogram chart is shown representing the tenuring distribution (total size across ages) for the selected cycle.
- No GC cycle selected: An informational message is displayed to prompt the user to select a cycle.
- Multiple GC cycles selected: An informational message is displayed indicating that only a single cycle can be viewed at a time.
This enhancement improves visibility into object tenuring during individual GC cycles. 

<img width="1174" height="599" alt="Screenshot 2025-10-15 at 16 51 19" src="https://github.com/user-attachments/assets/76ce69c2-60eb-48c8-be9f-6387cbfa7c42" />

<img width="1174" height="599" alt="Screenshot 2025-10-15 at 16 51 34" src="https://github.com/user-attachments/assets/a5fc9bc9-fa72-42c9-aeb2-ecad21e4ac66" />

<img width="1174" height="599" alt="Screenshot 2025-10-15 at 16 51 57" src="https://github.com/user-attachments/assets/63ffba47-8e08-430a-9a28-11473b59e6dc" />

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Commit messages:
 - 6004: Should add tenuring summary to the GC visualization

Changes: https://git.openjdk.org/jmc/pull/679/files
  Webrev: https://webrevs.openjdk.org/?repo=jmc&pr=679&range=00
  Issue: https://bugs.openjdk.org/browse/JMC-6004
  Stats: 94 lines in 9 files changed: 94 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jmc/pull/679.diff
  Fetch: git fetch https://git.openjdk.org/jmc.git pull/679/head:pull/679

PR: https://git.openjdk.org/jmc/pull/679