proxmox: contract and observability tests, integration test, testing docs

The contract sweep in provider_test.go: every method and Check returns
within a second of a cancel, every wrapErr path carries the configured
name, op and id, the V0/V1/V2 logging tiers and the no-op lines, and a
Get over the real client whose HTTP spans are children of provider.get.
proxmox_integration_test.go (-tags=integration) holds TestProxmox_lifecycle
and TestProxmoxCheck_realHost; both compile and skip without
PROXMOX_TEST_*, and have not run against a host yet. make
test-integration-proxmox runs them. docs/testing.md gains the proxmox,
nocloud and keyedlock rows, the Live Proxmox gaps and the integration
section; spec entry 21's section 11 list is ticked.

Waits that could hang the package under a mutation are bounded: the
concurrent-Create loop and eight direct blocking calls in older tests.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/proxmox-provider-spec.md

@@ -781,26 +781,28 @@ within the budget and its `UID` and `CreatedAt` equal what Create wrote;
 remain; an HTTP span is a child of `provider.create` and no span attribute
 carries the cloud-init text.
 
-Contract §11 list, with the planned test for each item (Phase 8 ticks them
-once they exist):
+Contract §11 list, with the test for each item. Every name below exists
+(Phase 8 checked each with a grep for `func <name>(`). The two integration
+tests compile under `-tags=integration` but have not run against a host
+yet; Phase 10 runs them.
 
-- [ ] repeat `Create`: `TestCreate_repeatReturnsSameIDAndCreatesNothing`
-- [ ] `Get` after `Delete`: `TestGet_afterDeleteReturnsNotFound`
-- [ ] `Delete` twice: `TestDelete_twiceSucceeds`
-- [ ] malformed ID: `TestParseProviderID_malformed`, `TestGet_malformedIDIsPermanent`, `TestDelete_malformedIDIsPermanent`
-- [ ] unknown state maps to `StateStopped`: `TestMapState_table`, `TestGet_unknownStateIsStopped`
-- [ ] `StateRunning` requires an IP: `TestGet_runningWithoutIPIsProvisioning`, `TestGet_runningWithIPIsRunning`
-- [ ] `UID` and `CreatedAt` read back: `TestGet_readsUIDAndCreatedAtFromBackend`
-- [ ] `ListByTag` excludes unmarked instances: `TestListByTag_excludesUnmarkedVMs`, `TestListByTag_emptyUIDStillListed`
-- [ ] `Get` during an in-progress delete: `TestGet_duringDeleteStillReturnsInstance`
-- [ ] `Get` during an asynchronous operation or lock: `TestGet_lockedIsTransientNeverNotFound`, `TestGet_midCloneNamelessEntryIsTransient`
-- [ ] never started is never `StateStopped`: `TestCreate_returnsOnlyWhenRunning`
-- [ ] cancelled `ctx` returns promptly: `TestProvider_cancelledContextReturnsPromptly`, `TestClient_cancelledContextReturnsPromptly`
-- [ ] `classify` table with captured responses: `TestClassify_table`
-- [ ] Checker reasons, expired `ctx`, stable order: `TestCheck_reasonsTable`, `TestCheck_expiredContextReturnsPromptly`, `TestCheck_oneEntryPerNodeInConfigOrder`
-- [ ] sentinel tests for `CloudInit` and the credential: `TestCreate_cloudInitSentinelNeverLoggedOrInErrors`, `TestClient_tokenNeverInErrorsOrLogs`
-- [ ] child spans under the operation span: `TestTracing_httpSpansUnderOperationSpan`, `TestClient_childSpanUnderParent`
-- [ ] real-backend lifecycle test: `TestProxmox_lifecycle` and `TestProxmoxCheck_realHost` in `proxmox_integration_test.go`
+- [x] repeat `Create`: `TestCreate_repeatReturnsSameIDAndCreatesNothing`
+- [x] `Get` after `Delete`: `TestGet_afterDeleteReturnsNotFound`
+- [x] `Delete` twice: `TestDelete_twiceSucceeds`
+- [x] malformed ID: `TestParseProviderID_malformed`, `TestGet_malformedIDIsPermanent`, `TestDelete_malformedIDIsPermanent`
+- [x] unknown state maps to `StateStopped`: `TestMapState_table`, `TestGet_unknownStateIsStopped`
+- [x] `StateRunning` requires an IP: `TestGet_runningWithoutIPIsProvisioning`, `TestGet_runningWithIPIsRunning`
+- [x] `UID` and `CreatedAt` read back: `TestGet_readsUIDAndCreatedAtFromBackend`
+- [x] `ListByTag` excludes unmarked instances: `TestListByTag_excludesUnmarkedVMs`, `TestListByTag_emptyUIDStillListed`
+- [x] `Get` during an in-progress delete: `TestGet_duringDeleteStillReturnsInstance`
+- [x] `Get` during an asynchronous operation or lock: `TestGet_lockedIsTransientNeverNotFound`, `TestGet_midCloneNamelessEntryIsTransient`
+- [x] never started is never `StateStopped`: `TestCreate_returnsOnlyWhenRunning`
+- [x] cancelled `ctx` returns promptly: `TestProvider_cancelledContextReturnsPromptly` (every method and `Check`, blocked on the first seam call, plus Create and Delete blocked mid-operation), `TestClient_cancelledContextReturnsPromptly`
+- [x] `classify` table with captured responses: `TestClassify_table`
+- [x] Checker reasons, expired `ctx`, stable order: `TestCheck_reasonsTable`, `TestCheck_expiredContextReturnsPromptly`, `TestCheck_oneEntryPerNodeInConfigOrder`
+- [x] sentinel tests for `CloudInit` and the credential: `TestCreate_cloudInitSentinelNeverLoggedOrInErrors`, `TestClient_tokenNeverInErrorsOrLogs`, and `TestLogging_v0SilentV1OutcomeV2Detail` over a whole lifecycle at every level
+- [x] child spans under the operation span: `TestTracing_httpSpansUnderOperationSpan`, `TestClient_childSpanUnderParent`
+- [x] real-backend lifecycle test: `TestProxmox_lifecycle` and `TestProxmoxCheck_realHost` in `proxmox_integration_test.go` (compiled, not yet run)
 
 Tests that cover the Phase 0 corrections specifically, in addition to the
 plan's per-phase lists: