Fleet UI: Add dynamic categories to edit software modal

[RachelElysia]

Issue

Part of #39018
Closes #46371

Description

• Replace hardcoded category list in CategoriesSelector with a useQuery fetch against the self-service categories API for the current fleet.
• Add empty state with an "Add category" link to /software/library/categories when the fleet has no categories.
• Render DataError when the categories fetch fails (retry: false so users see the error fast instead of waiting through 4 retries).
• Handle "some or all of the categories provided" BE error on edit save.
• Cap the categories list at 210px max-height with inner scroll so the last row peeks; apply the same 210px to TargetLabelSelector's checkbox list per Figma dev note.
• Static fallback path (no teamId passed) preserves the existing hardcoded list for VPP/Android/FMA forms until they're wired up separately.

Screen recording

Screen.Recording.2026-06-01.at.4.53.01.PM.mov

Testing

• Added/updated automated tests
• QA'd all new/changed functionality manually

[codecov]

Codecov Report

❌ Patch coverage is 90.47619% with 2 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (feat/39018-self-service-categories@abd3821). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
...wareTitleDetailsPage/EditSoftwareModal/helpers.tsx	0.00%	2 Missing ⚠️

Additional details and impacted files

@@                          Coverage Diff                          @@
##             feat/39018-self-service-categories   #46601   +/-   ##
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  Coverage                                      ?   66.86%           
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  Files                                         ?     2810           
  Lines                                         ?   223765           
  Branches                                      ?    11534           
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  Hits                                          ?   149618           
  Misses                                        ?    60592           
  Partials                                      ?    13555           

Flag	Coverage Δ
frontend	56.92% <90.47%> (?)

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