Refactor getValidTarget to return a list of items

[javorszky]

Proposed changes

Closes #8708

Checklist

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• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[Copilot]

Pull request overview

This PR refactors the getValidTargets function to return a list of DNSTarget objects instead of a simple string slice and a separate record type. The new structure combines the target address with its record type (A, AAAA, or CNAME), allowing the system to handle multiple record types for a single DNS endpoint.

Changes:

• Modified getValidTargets to return extdnsapi.Targets (slice of DNSTarget structs) instead of a string slice and separate record type
• Updated buildDNSEndpoint to group targets by record type and create separate endpoints for each type
• Introduced new DNSTarget type with Type and Address fields to replace the simple string-based Targets type

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
pkg/apis/externaldns/v1/types.go	Introduced DNSTarget struct and changed Targets type from []string to []DNSTarget
pkg/apis/externaldns/v1/zz_generated.deepcopy.go	Added auto-generated deepcopy methods for new DNSTarget type
pkg/apis/externaldns/validation/externaldns.go	Updated validateTargets and isUnique to accept []string instead of v1.Targets
pkg/apis/externaldns/validation/externaldns_test.go	Updated test cases to use []string instead of v1.Targets for target values
internal/externaldns/sync.go	Refactored getValidTargets to return typed targets and updated buildDNSEndpoint to collate targets by type
internal/externaldns/sync_test.go	Updated tests to expect new DNSTarget structure and removed record type assertions

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[codecov]

Codecov Report

❌ Patch coverage is 45.94595% with 20 lines in your changes missing coverage. Please review.
✅ Project coverage is 53.88%. Comparing base (8126541) to head (110e230).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/externaldns/sync.go	42.85%	20 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8869      +/-   ##
==========================================
- Coverage   53.93%   53.88%   -0.05%     
==========================================
  Files          91       91              
  Lines       18627    18628       +1     
==========================================
- Hits        10046    10038       -8     
- Misses       8049     8059      +10     
+ Partials      532      531       -1     

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