refactor: share frontend test setup and avoid duplicate CI

[vriesd]

Why

Four App test suites repeated the same desktop API mocks, reset behavior, and deferred-promise helper. An open pull request also triggered the full check matrix twice, once for its branch push and once for the pull request.

Scope

• Share the typed desktop API test harness while keeping per-test overrides and fixture seeds local.
• Keep pull-request checks and limit push checks to main and v* tags.
• Remove 361 net lines across the test setup and workflow changes.

Blast Radius

Application behavior and release checks are preserved. Test mock defaults are unchanged. The production frontend bundle is byte-for-byte identical to the base commit's bundle.

Verification

• All 260 frontend tests pass.
• Typecheck, lint, production build, workflow pin verification, and git diff --check pass.
• Compared every production bundle file and SHA-256 against 84b6c1b; all files are identical.
• Independent review found no blocking issues.

This is the first unit of the Echo complexity reduction. Recording and settings contract changes will be reviewed separately.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-05T07:24:08.417020Z	617b92f	PR opened

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[vriesd]

PASS

Independent shipping verification for PR134 (refactor/echo-test-ci).

Base: 84b6c1b2e1203c81c5e972fb2d75d5a87ea7d18c
Head: 617b92f87bd918efe5a87ab132d7c9016784a2de
Patch-id: f3073c1564f5b54ffc5addc0be5a7cd72c789a1e

Evidence:

• git diff --check 84b6c1b..617b92f passed.
• npm test -- App.test.tsx app/AppSettings.test.tsx app/AppSetup.test.tsx app/AppShortcut.test.tsx passed: 4 files, 133 tests.
• npm run typecheck passed.
• npm run lint passed.
• python3 scripts/verify-workflow-pinning.py --self-test && python3 scripts/verify-workflow-pinning.py passed.
• Inspected /tmp/echo-simplify/unit1-bundle-equivalence.json: production frontend bundle equivalence recorded as byte-identical across 11 files.

Verdict: PASS. I found no blockers for merge.