ddns-scripts: fix updating IPv6 for netcup

[beedaddy]

Fixes #30387
Uses suggested fix from #30387 (comment)

📦 Package Details

Maintainer: @feckert
_{(You can find this by checking the history of the package Makefile.)}

Description:

Fixes #30387
Uses suggested fix from #30387 (comment)

🧪 Run Testing Details

• OpenWrt Version: 25.12.5
• OpenWrt Target/Subtarget:
• OpenWrt Device: GL.iNet Flint 2

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✅ Formalities

• I have reviewed the CONTRIBUTING.md file for detailed contributing guidelines.

If your PR contains a patch:

• It can be applied using git am
• It has been refreshed to avoid offsets, fuzzes, etc., using

  make package/<your-package>/refresh V=s

• It is structured in a way that it is potentially upstreamable
  _{(e.g., subject line, commit description, etc.)
  We must try to upstream patches to reduce maintenance burden.}

[openwrt-ai]

Reviewed 1 new commit.

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Generated by Claude Code

[openwrt-ai]

Commit checks

• 4eb2e6f "ddns-scripts: apply suggestion from @openwrt-ai" — subject describes the review workflow, not the change. Say what it does (e.g. ddns-scripts: fix typo in netcup comment), or fold it into ac80481.
• f73c532 "ddns-scripts: apply suggestion from @openwrt-ai" — same; this one changes the record-match comparison to the new IP, which is the substance of ac80481 and belongs squashed into it rather than as a follow-up with an unrelated subject.

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Generated by Claude Code

[beedaddy]

Sorry—getting my first PR formally correct was a bit of a struggle. But I think it's ok now.
@feckert What do you think?

[openwrt-ai]

Commit checks

• 40c2e68 "ddns-scripts: fix updating IPv6 for netcup: update to 2.8.5" — subject stacks two scopes behind two colons. Precedent in this package splits them into a fix commit plus a bump commit (3aca374 + 774c01b "ddns-scripts: update to 2.8.4"); the body should also state what the fix does instead of only linking the issue comment.

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Generated by Claude Code

[nmeyerhans]

This looks reasonable to me.

[openwrt-ai]

Reviewed 1 new commits; no new issues found.

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Generated by Claude Code

[feckert]

Be careful not to exceed the 80-character limit in the commit message.
Please update the commit with:

ddns-scripts: fix updating IPv6 for netcup

Fix the netcup DDNS updater when comparing an existing
IPv6 record to the current address.

The previous logic relied on REGISTERED_IP and required it
to be set, but that value is not always available or reliable for
IPv6 records. As a result, the updater could wrongly skip or
fail to update AAAA entries.

This change:

-     Removes the hard dependency on REGISTERED_IP
-     Compares record type and hostname before evaluating the IP
-     Normalizes IPv6 addresses before comparison
-     Exits early when no update is required

Fixes #30387

Signed-off-by: Martin Brodbeck <martin@brodbeck-online.de>

In this commit, please increase only the PKG_RELEASE by one, not the PKG_VERSION. This is a change made in a provider and not a change to the core of the ddns-scripts.

@beedaddy Everything else looks good. If you make that change, I'd merge it as soon as possible.