fix: aggregate xRoute/xPolicy statuses across GWCs in gateway-api runner

[y-rabie]

First PR split of #7307. Includes only changes in the gateway-api runner.
E2e tests are included in the second PR.

[codecov]

Codecov Report

❌ Patch coverage is 12.76596% with 123 lines in your changes missing coverage. Please review.
✅ Project coverage is 72.39%. Comparing base (0fa26d7) to head (f8dd034).

Files with missing lines	Patch %	Lines
internal/gatewayapi/runner/runner.go	0.00%	121 Missing ⚠️
internal/gatewayapi/extensionserverpolicy.go	90.00%	1 Missing and 1 partial ⚠️

❌ Your patch check has failed because the patch coverage (12.76%) is below the target coverage (60.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7557      +/-   ##
==========================================
- Coverage   72.43%   72.39%   -0.04%     
==========================================
  Files         232      232              
  Lines       34307    34373      +66     
==========================================
+ Hits        24849    24884      +35     
- Misses       7682     7715      +33     
+ Partials     1776     1774       -2     

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[arkodg]

hey @y-rabie I agree with the overall logic here, suggesting improvements in the algo to avoid the nested for loops

• can replace the .Store with an internal Merge
• common state can be stored in map with status ptr as values

[y-rabie]

@arkodg Apologies I don't think I get what you're saying. Can you illustrate further?

[zhaohuabing]

Hi @y-rabie I guess this is what @arkodg is asking about (please correct me if I'm misunderstanding anything @arkodg 🙂 ) :

Optimize the current two-level loop by using a map, reducing the lookup of the inner loop from O(n) to O(1), and avoid consuming more memories by storing ptr to the original status instead of copying its value.

					for _, ar := range aggregatedResult.HTTPRoutes {
						if utils.NamespacedName(httpRoute) == utils.NamespacedName(ar) {
							aggregatedRoute = ar
							break
						}
					}
					// If already found (because processed in an earlier gatewayclass), append its status parents.
					// Otherwise, append it to the list of *Routes in the accumulated result.
					if aggregatedRoute != nil {
						aggregatedRoute.Status.Parents = append(aggregatedRoute.Status.Parents, httpRoute.Status.Parents...)
					} else {
						aggregatedRoute = httpRoute
						aggregatedResult.HTTPRoutes = append(aggregatedResult.HTTPRoutes, aggregatedRoute)
					}