PhoenixmlDb.Core 1.5.0

• net10.0

  • No dependencies.

• net8.0

  • No dependencies.

Metadata becomes namespace-qualified end to end. **Breaking**: the metadata surfaces on
`IContainer`, `IWriteTransaction` and `IDocument` change shape, as does `AddMetadataIndex` and the
persisted index-config format.

### Why this is breaking rather than additive

The old surface keyed metadata by a bare string and valued it as `object`. Two applications sharing
a database could not both use a name as ordinary as `status`, and — more seriously — the engine had
no single answer for what a metadata value *was*. A stored value was JSON; an indexed value was
typed XDM. Those are different comparisons, so adding an index could change which documents a query
returned, not merely how quickly it found them. That is not a defect an additive API can fix: the
two encodings had to stop existing, which means the surface that produced them had to go.

### The three-tier surface

Metadata names are now `XdmQName` and values `XdmValue`, exposed at three levels of explicitness:

```csharp
// local name, resolved against the container's default namespace
await container.SetMetadataAsync("invoice.xml", "status", "pending");

// typed descriptor — namespace and CLR type come from the property
await container.SetMetadataAsync("invoice.xml", DcTerms.Creator, "lucas");

// fully explicit
await container.SetMetadataAsync("invoice.xml", qname, XdmValue.From("application/xml"));
```

`ContainerOptions.DefaultMetadataNamespace` sets what unqualified names resolve to, defaulting to
`https://schemas.phoenixml.dev/2026/meta`. Set it to your own application namespace and a common
name such as `status` can no longer collide with another application's.

`GetAllMetadataAsync` returns a `MetadataCollection` rather than
`IReadOnlyDictionary<string, object>`, so a caller can finally separate a namespace from a local
name — the old shape handed back `"ns:name"` as one unsplittable string. `GetMetadataByNamespaceAsync`
is new, and is served by a cursor range over the namespace key prefix rather than by fetching all of
a document's metadata and filtering it.

`DocumentOptions.Metadata` is now `IReadOnlyDictionary<XdmQName, XdmValue>?`.

### Indexes are qualified too

`AddMetadataIndex` takes an `XdmQName`. An index that cannot say *which* `status` it covers is the
same collision in a different place, and — because the store keys by qualified name — a bare-named
index would answer for documents it does not describe. With one key model on both sides, declaring
an index is a pure performance decision.

The persisted index configuration records the namespace alongside the local name. A configuration
written by an earlier version is rejected with an explanatory error rather than reinterpreted:
defaulting the namespace would silently point an index at a different key than the store writes.

### Removed

`IContainer.SetIndexedValuesAsync` is deleted rather than ported. Its default interface
implementation returned a completed task for any implementation without indexing, so a caller could
not distinguish a successful write from a no-op; it also stored its values as a single JSON array
while indexing each element separately. Multi-valued metadata returns as a deliberate feature or
not at all.

### Notes

Two parameter names could not be used as intended: CA1716 rejects `property` and `namespace` on
virtual and interface members because they collide with reserved keywords in other .NET languages.
They are `descriptor` and `namespaceId`. Positional call sites are unaffected.