Add vertical tabs item padding control

[BobbyWang0120]

Description

Adds a synced appearance.vertical_tabs.item_padding setting and a vertical-tabs settings popup slider for adjusting the inner padding of vertical tab and pane rows. The control sits under Density, shows the current pixel value, and includes a reset button that restores the 8px default.

This helps users with many panes or agent sessions make the vertical sidebar more compact without changing horizontal tabs.

Linked Issue

Closes #11941

• The linked issue is labeled ready-to-spec or ready-to-implement.
  Note: I created Add configurable item padding for vertical tabs #11941, but this account does not have permission to add repo labels.
• Where appropriate, screenshots or a short video of the implementation are included below.

Testing

• cargo fmt --check --package warp
• cargo clippy -p warp --lib -- -D warnings
• cargo test -p warp vertical_tabs_item_padding --lib
• cargo check -p warp --lib
• git diff --check origin/master...HEAD
• I have manually tested my changes locally with ./script/run

Screenshots / Videos

Agent Mode

• Warp Agent Mode - This PR was created via Warp AI Agent Mode

CHANGELOG-IMPROVEMENT: Added a vertical tabs item padding control to make dense sidebars easier to scan.

Co-Authored-By: Warp agent@warp.dev

[BobbyWang0120]

Maintainers: could someone please add the ready-to-implement label to the linked issue #11941 when you have a moment? I don’t have permission to apply labels on upstream issues, and Warp’s PR checklist asks for the linked issue to be marked ready-to-spec or ready-to-implement so review can move forward. Thank you!

[oz-for-oss]

@BobbyWang0120

This PR is not linked to an issue that is marked with ready-to-implement.

Issue-state enforcement details:

• Associated same-repo issues checked: Add configurable item padding for vertical tabs #11941

• Required readiness label: ready-to-implement

Readiness check:

• Add configurable item padding for vertical tabs #11941: missing ready-to-implement; readiness labels present: none

To continue, link this PR to a same-repo issue such as Closes #123 in the PR description, and make sure that issue has ready-to-implement.

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[oz-for-oss]

@BobbyWang0120

This PR is not linked to an issue that is marked with ready-to-implement.

Issue-state enforcement details:

• Associated same-repo issues checked: #11941

• Required readiness label: ready-to-implement

Readiness check:

• #11941: missing ready-to-implement; readiness labels present: none

To continue, link this PR to a same-repo issue such as Closes #123 in the PR description, and make sure that issue has ready-to-implement.

Powered by Oz

[github-actions]

Hi @BobbyWang0120 — a reviewer requested changes on this PR and it hasn't had activity from you in 7 days. When you get a chance, please push updates or reply to the review so a reviewer can take another look. Without activity, this PR will be automatically closed after 30 days of inactivity.