fix(ui): slide the detail tab indicator instead of morphing glass

[KafuChino123]

Problem

The detail tab bar in the toolbar played an exaggerated stretch on every tab switch — most visible on the four-tab Containers view — and the first switch after a cold launch was worse still. The Runners detail bar was unaffected because it uses a native segmented Picker, where AppKit owns the indicator.

Affected views: Containers, Volumes, Images (Docker), Sandboxes, Machines — everything going through DetailTabPicker.

Root cause

Two independent departures from the documented Liquid Glass contract, compounding:

1. GlassEffectContainer(spacing:) was being used as a layout gap. It is a blend threshold — Apple: "As shapes near one another, their paths start to blend into one another. The higher the spacing, the sooner blending begins." It was set to tabCount * AppMetrics.detailTabSegment:

View	Tabs	spacing	HStack spacing
Containers	4	320pt	2pt
Images	3	240pt	2pt
Sandboxes	6	480pt	2pt

Applying Liquid Glass to custom views: "A spacing value on the container that's larger than the spacing of an interior HStack … causes Liquid Glass effects to blend together at rest." Apple's own example pairs GlassEffectContainer(spacing: 40) with HStack(spacing: 40). The blend field here covered the entire bar, so the indicator blended against segments it was nowhere near.

2. One shared glassEffectID over a per-segment .regular ↔ .identity toggle. GlassEffectTransition.matchedGeometry: "this transition applies additional scale and offset effects to content when the identity of the shape does not change but its content does." "selected-detail-tab" stayed constant while the segment beneath it changed — precisely that trigger.

Fix

Render one persistent glass capsule and position it with matchedGeometryEffect against the selected segment: each segment is a geometry source, and a single Color.clear.glassEffect(.regular.interactive()) background follows id: selection.

The pill now moves instead of appearing and disappearing, so there is no morph to overshoot and no appearance transition to misfire on first mount. GlassEffectContainer is dropped — it exists to blend multiple effects, and there is now one.

Animation also tightened from 0.3s to 0.2s, closer to the native indicator's pace. reduceMotion handling and the accessibilityRepresentation segmented Picker are unchanged.

Verification

• make build, make lint (0 violations), make test (91 tests / 10 suites) all pass on this branch.
• Manually verified in ArcBox Dev across several cold launches — cold-start first open, Containers (4 tabs), and repeated switching. Confirmed by the reporter.
• No test added: this is animation geometry with no branching logic to assert against. The behaviour is only observable in a running window.

Note for reviewers

The pill reads as a cleaner slide than before — the liquid squish is gone. That is intentional, and tunable independently of the bug. If a glassier feel is wanted back, the lever is the animation curve, not the container spacing.

---

Also included: curate the 1.35.0 highlights

This PR carries a second, unrelated commit because CI on master is currently red for every PR and this one cannot be verified without it.

Release PR #382 (chore(master): release 1.35.0, 4e034ec) merged with its own check already red, leaving ## [1.35.0] in CHANGELOG.md without a ### Highlights section while .release-please-manifest.json names 1.35.0. pr.yml:90 therefore fails with release 1.35.0 has no non-empty ### Highlights section, and that step runs before Lint, Build (Debug) and Run Tests — so no PR reaches the compiler. The release DMG extracts the same section to feed Sparkle's update dialog and refuses to build without it, so 1.35.0 cannot be packaged either.

The added section is written from what 1.35.0 actually shipped — Fleet device auth and runner management (#320), authoritative sandbox port reconciliation (#374), and telemetry identification with the Privacy toggle ordering (#367). Build, docs and CI-only entries are left out; this text is what users see in the update dialog.

cargo xtask release notes --version "$(jq -r '."."' .release-please-manifest.json)" — the exact CI invocation — now succeeds. Verified green on its own branch before consolidation: Build & Test passed in 8m48s with Verify curated release highlights, Lint, Build (Debug) and Run Tests all ✓.

Reviewers: the changelog wording is the part worth reviewing, since it ships verbatim to users. One sentence is a deliberate judgment call — it states plainly that a signed-in account is identified by email and name while analytics is on. #367 made that change and also corrected the Privacy toggle's caption, which had claimed no personal data was collected. Reword or drop it if you'd rather it not appear there.

Happy to split this back out if you'd rather land the unblock on its own — it was originally #389.

[greptile-apps]

Greptile Summary

The PR replaces the per-segment Liquid Glass morph with one persistent capsule that follows the selected detail tab using matched geometry, while preserving reduced-motion and accessibility behavior.

• Removes the oversized GlassEffectContainer blend field and per-segment glass toggling.
• Shortens the selection animation and centralizes the segment gap.
• Adds curated highlights for the 1.35.0 changelog.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
ArcBox/Components/DetailTabPicker.swift	Reworks the shared detail-tab indicator into a single matched-geometry glass capsule without an accepted blocking issue.
CHANGELOG.md	Adds release highlights without affecting application behavior.

_{Reviews (2): Last reviewed commit: "chore(release): curate the 1.35.0 highli..." | Re-trigger Greptile}