Sync wave 10

.claude/skills/fix-issue/findings/mdl-backend.jsonl

@@ -148,3 +148,4 @@
 {"area": "mdl/backend", "date": "2026-09-29", "symptom": "ALTER ASSOCIATION / CREATE OR MODIFY ASSOCIATION / RENAME / mxcli layout on a Studio Pro module turns every API-exported entity in the module Hidden and rewrites every entity's access rules (50 of 93 elements in TestApp WorkflowCommons changed for a no-op write); ALTER ENTITY and MOVE ENTITY reset the target's (and its attributes') export level the same way. mx check stays clean (#801)", "cause": "entityToGen / attributeToGen / assocToGen SET ExportLevel \"Hidden\", and a property the rebuild sets is dirty and wins over the carried raw bytes; UpdateDomainModel rebuilt every entity and association, not only the one named. Member-access writers set only the reference in use, while Studio Pro writes both Attribute and Association keys (the unused one as \"\"), so every rebuilt rule differed from its stored self", "file": "mdl/backend/modelsdk/domainmodel_carry.go", "fix": "UpdateDomainModel passes an entity/association through as its stored element when the semantic model equals the stored one read back (entityUnchanged/assocUnchanged, ID- and nil/empty-insensitive semanticEqual). Rebuilds of existing entities (UpdateEntity, UpdateDomainModel, MoveEntity) go through carryStoredEntity: raw + child identity + stored ExportLevel (entity and carried attributes) + unchanged access rules substituted by the stored element, changed ones keep $ID/caption/documentation. carryStoredAssociation: raw + ExportLevel + unchanged delete behaviour. DomainModels$MemberAccess registers EmptyStringFields Attribute/Association", "insight": "A raw carry only preserves what the converter does NOT set; every constant a converter writes (here ExportLevel \"Hidden\") is still reset on the carried element, so audit the converter's Set* constants, not only unmodelled keys. The whole-list rebuild shape needs an 'unchanged -> pass the stored element' short-circuit or its blast radius is the unit. Invisible on mxcli-authored content, where the stored value IS the constant: TestApp is the only fixture with API entities (WorkflowCommons) and has no API attribute, so the attribute case was set up on top of it. The roundtrip harness had 87 getput entries (#721 B and TestApp associations) that were this bug", "refs": ["ako/mxcli#801", "ako/mxcli#721"], "test": "TestIssue801_UpdateDomainModelChangesOnlyTheAlteredElement, TestIssue801_OtherEntityRebuildsKeepExportLevel"}
 {"area": "mdl/backend", "date": "2026-09-29", "symptom": "describe -> exec, CREATE OR MODIFY or an ALTER that rebuilds the document turns an API-exported document Hidden: enumerations, pages, layouts, rules, view-entity OQL source documents, import/export mappings, JSON structures, published and consumed REST services, scheduled events, workflows, database connections, business event services, data transformers, queues, regular expressions and agent-editor documents. The run reports success, mx check is clean; the module's public surface silently shrinks. A workflow's own `export level API` clause was a no-op on create and on rewrite.", "cause": "Each rewrite converter builds a fresh document and writes ExportLevel as a constant (\"Hidden\"), or passes the semantic model's value where the executor itself filled in \"Hidden\" (mappings, database connection, business events), and the unit is replaced wholesale. MDL has no export-level spelling for most of these kinds, so describe cannot print it and the executed script cannot restore it. workflowToGen ignored wf.ExportLevel entirely. The round-trip harness could not see it: every document in TestApp and PedApp is Hidden, the constant itself.", "file": "mdl/backend/modelsdk/export_level_carry.go", "fix": "One byte-level carry, keepStoredExportLevel(unitID, contents): replaces only the top-level ExportLevel element of the freshly encoded rewrite with the stored value, copying every other element verbatim, and never adds the key. Wired into every Update path that writes ExportLevel (UpdateEnumeration/Rule/Layout/ImportMapping/ExportMapping/JsonStructure/PublishedRestService/ConsumedRestService/DataTransformer/DatabaseConnection/BusinessEventService, writeCustomBlob update, WriteViewEntitySourceDocument update; page via carryStoredPageHeader). Kinds with an MDL spelling (workflow, scheduled event, queue, regular expression) use keepStoredExportLevelUnlessSet: an authored level wins. workflowToGen now writes orDefault(wf.ExportLevel, \"Hidden\").", "insight": "A fixture-driven round trip is blind to any constant that happens to equal every fixture value: 775 TestApp documents round-tripped while 10 kinds hid API documents. Set the subject to the non-default value first (here: patch ExportLevel to API on the working copy) and run both the plain describe output and an edited one, because an elided unchanged write passes a converter that still writes the constant. Carrying at the encoded-bytes level covers gen-typed, newElem-built and hand-serialized writers with one helper, where a gen setter per converter would have needed three mechanisms.", "refs": ["ako/mxcli#816", "ako/mxcli#801", "ako/mxcli#812"], "test": "mdl/backend/modelsdk/issue816_export_level_test.go (TestUpdatePaths_KeepStoredExportLevel, 18 kinds); mdl/roundtrip/export_level_test.go (TestTestAppExportLevelSurvivesRoundTrip, -tags integration)"}
 {"date": "2026-09-30", "area": "mdl/backend", "symptom": "ako/mxcli#859 review of PR #864: after the built comparison landed, changing or adding `show page M.P with title = 'X'` in a `create or modify microflow` reported \"Unchanged microflow\" and wrote nothing, under mdl 0 and mdl 1 (main spliced it). Nothing warned.", "cause": "builtAsStored compares the declared flow and the stored flow both READ BACK through the codec, so any property the reader drops compares equal whatever either side holds. The ShowFormAction reader never read FormSettings.TitleOverride. Probing encode(built) against encode(readback(built)) over mdl-examples found the reader also dropped ExclusiveSplit/LoopedActivity ErrorHandlingType and a REST call's bound output variable (ResultHandling.ResultVariableName -> RestCallAction.OutputVariable), plus CallWebServiceAction (#861). Before the built comparison such a loss was a visible phantom re-splice; after it, a silently dropped edit.", "fix": "ReadBackMicroflow/ReadBackNanoflow re-encode what they read back and refuse (error -> statement diff, the pre-#859 path) when it is not the document first written, $IDs aside (sameWritten). The reader now reads TitleOverride, the split's and loop's ErrorHandlingType, and a bound REST call's OutputVariable, so those flows keep matching.", "insight": "A comparison made on both sides through the same lossy reader cannot see what the reader loses; the lost property becomes a change that is never written. When equality is decided after a decode, prove the decode lossless for the value at hand (write it again and compare bytes) and fall back when it is not. The probe that found the fields: diff encode(x) with encode(decode(encode(x))) over every mdl-examples flow.", "issue": "ako/mxcli#859", "file": "mdl/backend/modelsdk/microflow_readback.go, mdl/backend/modelsdk/microflow_read_actions.go, mdl/backend/modelsdk/microflow.go, mdl/roundtrip/flow_idempotent_shapes_test.go"}
+{"date": "2026-09-30", "area": "mdl/backend", "symptom": "ako/mxcli#843 (rehearsal M2): under mdl 1, `create or modify nanoflow … returns Boolean as $Done` over a nanoflow stored without a return variable refuses \"the stored document has no ReturnVariableName property … set it in Studio Pro\"; the same statement on a microflow reports \"set: ReturnVariableName\".", "cause": "mfmutator.SetHeader refuses any stated header key the stored document lacks (a key the project version does not declare makes the document unopenable). mxcli's nanoflow writer omits ReturnVariableName when the statement has no `as $Var`, while the microflow writer always writes it on 10+, so only nanoflows hit the refusal.", "fix": "Optional mfmutator.PropertyDeclarer on Deps; the codec deps answer from the metamodel version data (type, then Microflows$MicroflowBase; ReturnVariableName is 10.12+) against the project version, and SetHeader inserts the key after its predecessor in the encoder's order. No answer (MCP, unknown version) keeps the refusal.", "insight": "A refusal keyed on 'the stored document lacks the key' conflates 'this version has no such property' with 'the writer left it out'; the metamodel version data separates the two. Studio Pro 11 stores ReturnVariableName on every nanoflow (PedApp: 13 of 13), so adding it matches what Studio Pro writes.", "issue": "ako/mxcli#843", "file": "mdl/backend/mfmutator/header.go"}