Implement polygon drawing for web app

[cuongnt]

Summary
Implements end-to-end polygon drawing on the web app:

• Click map to add vertices with live preview overlay
• Complete/Cancel toolbar appears during drawing
• Saves polygon LOI to Firestore via Protobuf serialization
• Unhides the polygon drawing tool button

Changes

• geometry-data-converter.ts: model → Protobuf converters
• loi-data-converter.ts: LOI → Firestore document serializer
• data-store.service.ts: addOrUpdateLoi() method
• loi.service.ts: addPoint() updated, addPolygon() added
• map.component: vertex collection, preview overlay, toolbar UI
• drawing-tools.component: polygon button unhidden
• map.component.spec.ts: tests updated and added

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[gino-m]

Can you please attach a screen recording and a bug number so we can get more context?

[cuongnt]

I apologize, please disregard this request. I made a mistake. My intention was to display the drawn plots in the new plot creation module window on the Android app. I will pull a request for this in my next request. Sincerely, Cuong

…

On Wed, 29 Jul 2026 at 23:07, Gino Miceli ***@***.***> wrote: *gino-m* left a comment (google/ground-platform#2570) <#2570 (comment)> Can you please attach a screen recording and a bug number so we can get more context? — Reply to this email directly, view it on GitHub <#2570?email_source=notifications&email_token=AKOXPQULUIB5NR3AZMRSEXT5HIOLZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMJSGA2DAMJWHE22M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-5120401695>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AKOXPQVUWFKTPVGFNKIUF6T5HIOLZAVCNFSNUABFKJSXA33TNF2G64TZHMYTGMJQGI3TONRQHNEXG43VMU5TIOJVGQ2TQNZTGE2KC5QC> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/AKOXPQW5OK7DTC7KU424O735HIOLZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMJSGA2DAMJWHE22M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KUZTPN52GK4S7NFXXG> and Android <https://github.com/notifications/mobile/android/AKOXPQQPFBNDJZJUZUDKUMT5HIOLZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMJSGA2DAMJWHE22M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2K4ZTPN52GK4S7MFXGI4TPNFSA>. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.***>