don't write no-ops as new URL history items

[taylordowns2000]

Description

This pr closes #4812 by preventing no-ops (where previous URL == new URL) from being added as new URL history items.

Validation steps

1. Go to workflow list
2. Click into workflow
3. Click back
4. See that it works after a single click, not 3 clicks

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[github-actions]

Security Review ✅

• S0 (project scoping): N/A — change is entirely client-side history.pushState deduplication in assets/js/react/lib/use-url-state.ts:105, no data access.
• S1 (authorization): N/A — no new web-layer actions, controllers, or LiveView events introduced.
• S2 (audit trail): N/A — no config-resource writes; only browser URL/history behavior changed.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.3%. Comparing base (f590caa) to head (912c43b).

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #4813   +/-   ##
=====================================
  Coverage   90.3%   90.3%           
=====================================
  Files        444     444           
  Lines      22577   22577           
=====================================
+ Hits       20393   20396    +3     
+ Misses      2184    2181    -3     

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[lmac-1]

I added an extra commit to extend this fix to replaceSearchParams for housekeeping. Double checked and this shouldn't have any extra implications. Approved

[stuartc]

@taylordowns2000 I made a few tweaks here:

Two gaps with the guard/is the url the same. updateHash didn't have it, although it's not actually being called by anything right now which is weird but I'm hesitant to remove it because it's not impossible we will use hash state urls again and if used it'd still push a history entry on a no-op and could bring the stacking bug back. Routed that through a shared function guard too (nothing calls it yet, so just being safe).

The check was order-sensitive - it compared full URL strings, so if replaceSearchParams got the same params in a different order it didn't match and pushed a dupe anyway. Made the comparison ignore param order so a reorder counts as a no-op.

Added a little currentURL helper the three writers seed from - so there's one correct guard instead of two copies and one missing. Ended up being slightly less code overall. Added tests for the new cases too.