test(e2e): raise scroll-history pagination test timeout to 90s

[tellaho]

Overview

Category: fix (test infrastructure)
User Impact: No user-facing change — restores CI reliability for a budget-bound E2E test.

Problem: The E2E test scroll-history.spec.ts › channel intro stays hidden while paginating past the timeline cap is a budget-bound flake. It seeds ~2160 events and drives ~200 mouse.wheel iterations with 80ms settle waits — a genuinely heavy browser-scroll loop — against a hard 60s cap with near-zero headroom. It reliably passes on fast local hardware but tips over 60s on the slower GH-hosted runner.

Solution: Raise the per-test timeout from 60s → 90s to restore the ~3x margin the GH runner needs. One-line change plus an explanatory comment; nothing else touched.

Why this is a budget problem, not a regression

This test currently blocks #1229 (owner-pane activity gate), but the failure is not #1229's fault — the diagnosis:

• Local runs pass with room to spare. Ran the exact failing test 3× back-to-back at the same commit CI was on: 24.7s / 24.0s / 24.4s, all green — ~36s under the 60s cap.
• A passing CI run was already marginal. PR refactor(agents): replace avatar-clear boolean with AvatarState tri-state enum #1232 ran the byte-identical test and passed — but at 45.5s of the 60s cap, only ~15s of slack. Proof the test is genuinely on the edge regardless of which PR triggers it.
• fix(observability): gate agent observability on declared ownership, not key custody #1229 drew a slow runner. On fix(observability): gate agent observability on declared ownership, not key custody #1229 it timed out >60s ×3 — but the whole Smoke E2E (3) shard ran 7.2m vs refactor(agents): replace avatar-clear boolean with AvatarState tri-state enum #1232's 3.8m, i.e. that runner was ~2x slower across tests fix(observability): gate agent observability on declared ownership, not key custody #1229 never touches. Pure runner variance, not PR fallout.
• The spec is byte-identical to main (git diff origin/main on the file is empty); last touched by desktop: fix scrollback paging and visible history depth #1153 / fix(desktop): single-owner anchored scroll for dynamic loading #1115. This isn't fix(observability): gate agent observability on declared ownership, not key custody #1229's code.

So the test was always one slow runner away from red. 90s gives it the headroom CI needs.

Changes

File changes

desktop/tests/e2e/scroll-history.spec.ts
Raised testInfo.setTimeout(60_000) → 90_000 for the "channel intro stays hidden while paginating past the timeline cap" test, with a comment explaining the runner-slowdown / near-zero-headroom rationale.

Reproduction Steps

1. Check out main and run the affected test: pnpm --filter desktop test:e2e scroll-history.spec.ts -g "paginating past the timeline cap".
2. On fast local hardware it passes in ~24s. On a slower GH-hosted runner it can exceed the old 60s cap.
3. With this change the cap is 90s, restoring margin for the slow runner.

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Blocks-fix for #1229 — once this merges, #1229 rebases onto updated main and CI goes green.

Co-authored-by: Taylor Ho taylorkmho@gmail.com
Signed-off-by: Taylor Ho taylorkmho@gmail.com