Fix(4008): Set client id if empty on update extclient.

[VishalDalwadi]

Describe your changes

Fixes: #4008

Set client id if empty on update extclient.

Provide Issue ticket number if applicable/not in title

Provide testing steps

Checklist before requesting a review

• My changes affect only 10 files or less.
• I have performed a self-review of my code and tested it.
• If it is a new feature, I have added thorough tests, my code is <= 1450 lines.
• If it is a bugfix, my code is <= 200 lines.
• My functions are <= 80 lines.
• I have had my code reviewed by a peer.
• My unit tests pass locally.
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[tenki-reviewer]

Tenki Code Review - Complete

Risk: 🟢 Low (3/100) — no findings · 3 LOC across 1 file

Files Reviewed: 1
Findings: 0

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A minimal, correct defensive guard is added to updateExtClient that prevents a client from accidentally clearing its own ClientID when the update payload omits that field. No bugs or security issues are introduced.

Files Reviewed (1 files)

controllers/ext_client.go