added dispose() on some dialogs (fix memory leaks)

[exeea]

This PR fixes few memory leaks.
Added dispose() calls to:

• CostDisplayDialog
• WeightDisplayDialog
• ASConversionInfoDialog
• EntityReadoutDialog
• ASStatsDialog
• AutoResolveChanceDialog
• SBFStatsDialog

those are dialogs that are spawned every time, never reused.

[Copilot]

Pull Request Overview

This PR adds dispose() calls via overriding cancelAction() in both dialog classes to ensure proper resource cleanup when a cancel action is triggered.

• Overrides cancelAction() in WeightDisplayDialog to call dispose().
• Overrides cancelAction() in CostDisplayDialog to call dispose().

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
megamek/src/megamek/client/ui/dialogs/WeightDisplayDialog.java	Added cancelAction() override that calls dispose() for proper resource cleanup.
megamek/src/megamek/client/ui/dialogs/CostDisplayDialog.java	Added cancelAction() override that calls dispose() for proper resource cleanup.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 15 lines in your changes missing coverage. Please review.

Project coverage is 30.33%. Comparing base (e604a99) to head (1b7b3f8).
Report is 11 commits behind head on master.

Files with missing lines	Patch %	Lines
...mek/client/ui/dialogs/AutoResolveChanceDialog.java	0.00%	3 Missing ⚠️
...amek/client/ui/dialogs/ASConversionInfoDialog.java	0.00%	2 Missing ⚠️
...k/src/megamek/client/ui/dialogs/ASStatsDialog.java	0.00%	2 Missing ⚠️
...c/megamek/client/ui/dialogs/CostDisplayDialog.java	0.00%	2 Missing ⚠️
...megamek/client/ui/dialogs/EntityReadoutDialog.java	0.00%	2 Missing ⚠️
.../src/megamek/client/ui/dialogs/SBFStatsDialog.java	0.00%	2 Missing ⚠️
...megamek/client/ui/dialogs/WeightDisplayDialog.java	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##             master    #6959   +/-   ##
=========================================
  Coverage     30.32%   30.33%           
- Complexity    15859    15875   +16     
=========================================
  Files          2891     2891           
  Lines        283420   283434   +14     
  Branches      49329    49329           
=========================================
+ Hits          85958    85986   +28     
+ Misses       191837   191821   -16     
- Partials       5625     5627    +2     

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[Sleet01]

@exeea @rjhancock This is marked "For New Dev Cycle"; does that mean targeted at 0.50.07?

[Scoppio]

I'd prefer to see those in this release, since its memory leak related.

[HammerGS]

I'm good with including it

[Sleet01]

Looks good to me!