refactor(provider): bring opencode, muse, pi, core and testing in line with Effect conventions

[juliusmarminge]

Part of the provider-package audit: every module in provider-opencode, -muse, -pi, -core and -testing should now follow docs/internals/effect-services.md.

Shape interfaces and naming

• OpenCodeRuntimeShape is inlined into the service. Consumers use OpenCodeRuntime.OpenCodeRuntime["Service"].
• ServerProviderShape wasn't a service at all. It's renamed ManagedServerProvider, next to makeManagedServerProvider.
• provider-testing/host.ts defined a service in a camelCase module. It's now TestProviderHost.ts, exporting layer and TestProviderHostSettings, and its key matches the module.

State and services

• OpenCode's message-id counter was a pair of module-level lets. It's now a Ref owned by the adapter. Ordering only matters within one session, and one adapter owns each session. Uniqueness across adapters comes from the random suffix, as before.
• OpenCode2Client.readEvents and OpenCode v2 text generation yield HttpClient and ProviderHost instead of taking them as parameters.
• expandHomePathWith(value, path) took a service as a parameter and gave the same result as expandHomePath on Node. It's removed.

Imports

• effect/http, effect/process and effect/testing modules are imported as subpath namespaces in 34 files.

Left as is, deliberately

• managedProvider's refresh still uses orDie. The only typed error is a settings-read failure that no caller can recover from.
• OpenCodeRuntimeError still builds detail from cause.message (47 constructions, user-visible). That's a separate PR.
• The Muse SDK host stays a test-seam option. It doesn't depend on any Effect service.

Model: Claude Opus 5.5 via Claude Code in T3 Code.

🤖 Generated with Claude Code

---

[macroscopeapp]

Approvability

Verdict: Approved at 6bc94e1

Macroscope's review found this PR approvable — This is a broad but largely mechanical refactor to align private provider packages with Effect conventions. The limited production-path changes preserve existing path, HTTP, host, and provider behavior while making state ownership explicit, with no new capability, schema change, product-default change, deployment change, or static-analysis suppression.

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[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

ℹ️ The exact PR base did not have a successful artifact. Baseline uses the latest successful main measurement shown below.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	5.0 KiB	5.0 KiB	0 B (0.0%)	6.8 KiB	✅
Codex	Thread snapshot wire	3.8 KiB	3.8 KiB	0 B (0.0%)	4.9 KiB	✅
Codex	Live turn WebSocket wire	1.2 KiB	1.2 KiB	0 B (0.0%)	2.0 KiB	✅
Codex	Live turn WebSocket decoded	20.9 KiB	20.9 KiB	0 B (0.0%)	29.3 KiB	✅
Codex	Live turn messages	2	2	0 (0.0%)	8	✅
Claude	Total thread wire	5.0 KiB	5.0 KiB	+24 B (+0.5%)	6.8 KiB	✅
Claude	Thread snapshot wire	3.8 KiB	3.8 KiB	0 B (0.0%)	4.9 KiB	✅
Claude	Live turn WebSocket wire	1.2 KiB	1.2 KiB	+24 B (+2.0%)	2.0 KiB	✅
Claude	Live turn WebSocket decoded	21.2 KiB	21.2 KiB	+41 B (+0.2%)	29.3 KiB	✅
Claude	Live turn messages	1	2	+1 (+100.0%)	8	✅

Baseline: a669827 · PR result: 6bc94e1 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 108.5 KiB
• Claude decoded thread snapshot: 108.8 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.