ZubiSniffer - Sniffer UI Cleanup / Sticky Save
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Changes
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- Renamed the visible Packet Cap page/sidebar label to "Sniffer".
- Removed the Sniffer mode/view switch entirely. All observed non-hidden endpoints are shown.
- Removed the subtitle/truth-note text under the Sniffer title.
- Kept endpoint classification columns and evidence; only the obsolete view-mode path was removed.
- Kept interface switching Settings-only.
- Right-click hide now says "Hide IP from Sniffer" and Settings uses "Sniffer Hidden IPs" wording.
- Cleaned the Settings page by removing the extra Advanced Controls header/captions.
- Removed the embedded technical Capture category from the flattened Settings workspace; capture interface/runtime controls remain in the custom Settings cards.
- Removed verbose FULL IPv4/UDP visibility/manual-save explainer clutter from Capture Runtime.
- Added a sticky save bar that appears immediately when any non-live setting becomes dirty, with a SAVE CHANGES button that stays reachable without scrolling.
- Fixed login field geometry: username/password/API/password-change inputs use a consistent 40px height and centered vertical padding.
- Removed the obsolete TrafficViewMode/mode_accepts implementation and its tests.

Verification
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- Python compileall: PASS
- pytest: 74 passed
