Fix a bug where the pinned items banner could overlay the composer.

[pixlwave]

This PR puts the overlay on just the timeline, and not the timeline + composer. Probably not a final fix given the clipping that takes place, but good enough for now. Closes #3411.

Simulator.Screen.Recording.-.iPhone.SE.3rd.generation.-.2024-10-23.at.17.21.02.mp4

[github-actions]

	Warnings
⚠️	Some of the commits are missing ticket numbers. Please consider squashing all commits that don't have a tracking number.
⚠️	You seem to have made changes to views. Please consider adding screenshots.

Generated by 🚫 Danger Swift against cb5f5a1

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

❌ 2 Tests Failed:

Tests completed	Failed	Passed	Skipped
847	2	845	0

View the full list of 2 ❄️ flaky tests

PreviewTests test_loginScreen()

Flake rate in main: 26.91% (Passed 296 times, Failed 109 times)

Stack Traces | 6.95s run time

failed - Snapshot "matrix.org" does not match reference.

@−
"file:.../__Snapshots__/PreviewTests/test_loginScreen-iPhone-16-pseudo.matrix-org.png"
@+
"file:.../tmp/PreviewTests/test_loginScreen-iPhone-16-pseudo.matrix-org.png"

To configure output for a custom diff tool, use 'withSnapshotTesting'. For example:

    withSnapshotTesting(diffTool: .ksdiff) {
      // ...
    }

The percentage of pixels that match 0.8482666 is less than required 1.0
The lowest perceptual color precision 0.39937502 is less than required 0.98 (.../PreviewTests/Sources/PreviewTests.swift:84)

RoomScreenViewModelTests testPinnedEventsBanner()

Flake rate in main: 21.92% (Passed 57 times, Failed 16 times)

Stack Traces | 11.8s run time

Asynchronous wait failed: Exceeded timeout of 10 seconds, with unfulfilled expectations: "Awaiting publisher". (.../Sources/Extensions/XCTestCase.swift:43)

To view individual test run time comparison to the main branch, go to the Test Analytics Dashboard

[stefanceriu]

Nice and simple 👍