ci(e2e): Phase 4 — 7-cell matrix split + foundry/CDM full-deploy tests

[EnderOfWorlds007]

Summary

Phase 4 of the E2E redesign per docs-internal/2026-05-02-e2e-test-suite-design.md. Splits the single E2E job into a 6-cell matrix and adds a foundry full-deploy test.

What changed

• Matrix split: test-no-publish (4 parallel cells) + test-publish (2 serial cells, max-parallel: 1)
• pr-deploy-foundry — NEW full-deploy test for the EVM/Foundry backend, uses pre-committed bytecode + --no-contract-build (no forge needed in CI)
• mod.test.ts describe restructure — dot mod — clone (PR cell) vs dot mod — registry miss (future nightly cell)

Out of scope (deferred)

• pr-deploy-cdm: dropped pending a real rust-cdm fixture. The current fixture's target/flipper.contract is a stub; making CDM full-deploy work requires (a) a complete Cargo.toml so detectContracts can run, and (b) a committed target/<crate>.release.polkavm from a real cargo-contract build. Tracked as Phase 5 follow-up. Until then, CDM detection is covered by pr-preflight's detects CDM/Rust contracts type test, and the skip-build path is covered by unit tests.
• Phase 5 cells (hardhat full-deploy, multi-contract, modable, registry-miss as nightly, etc.)
• Phase 6 chaos cells (RPC failover, SIGINT)
• Phase 7 published-binary surface

Stacked on

• PR ci: E2E suite Phase 1 — reporting + tagging #82 (Phase 1, merged) — reporting + tagging
• PR tools(e2e): register-e2e-fixtures — Phase 3 of E2E redesign #84 (Phase 3, merged) — register-e2e-fixtures
• PR feat(deploy): --no-contract-build flag for CI without contract toolchains #86 (merged) — --no-contract-build flag

Test plan

• All 6 PR cells green: pr-install, pr-preflight, pr-deploy-frontend, pr-deploy-foundry, pr-mod, pr-init-session
• Critical path: ~14 min (publish chain serial); no-publish chain parallel
• Sticky comment shows per-cell rows correctly (verified across multiple pushes)
• Forensic uploads land per-cell (e2e-reports-<cell> artefact pattern)

[github-actions]

Dev build ready — try this branch:

curl -fsSL https://raw.githubusercontent.com/paritytech/playground-cli/main/install.sh | VERSION=dev/ci/e2e-phase-4-matrix-split bash

[github-actions]

E2E Test Pass · ✅ PASS

Tag: e2e-ci-pr · Branch: ci/e2e-phase-4-matrix-split · Commit: 466080f · Run logs

Cell	Result	Time
pr-preflight	✅ PASS	2m41s
pr-install	✅ PASS	0m35s
pr-deploy-foundry	✅ PASS	1m27s
pr-deploy-frontend	✅ PASS	17m16s
pr-mod	✅ PASS	1m19s
pr-init-session	✅ PASS	1m18s

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