deprecate(reader): mark VortexHandle.slice as internal escape hatch

The slice(long, long) method is on the public VortexHandle interface only
because ScanIterator and VortexInspector live in sibling packages and need
cross-package access to the raw backing MemorySegment of a file. It is not
part of the stability contract and would not survive a clean module
layout.

Until that consolidation happens (TODO), mark the method with @APinote
spelling out the situation and @deprecated(since="0.4.0", forRemoval=true)
so the IDE surfaces it as off-contract for any application code that
finds it via autocomplete.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: dfa1

reader/src/main/java/io/github/dfa1/vortex/io/VortexHandle.java

@@ -29,6 +29,19 @@ public interface VortexHandle extends Closeable {
 
     /// Returns a read-only view of bytes `[offset, offset+length)` within the file.
     /// Writes through the returned segment throw `UnsupportedOperationException`.
+    ///
+    /// @param offset the start offset in bytes
+    /// @param length the number of bytes to expose
+    /// @return a read-only [MemorySegment] view of the requested range
+    /// @apiNote <strong>Internal escape hatch.</strong> This method is on the public
+    /// {@link VortexHandle} interface only because {@link io.github.dfa1.vortex.scan.ScanIterator}
+    /// and {@link VortexInspector} live in sibling packages and need cross-package access to the
+    /// raw backing segment. It is not part of the supported stability contract; signatures and
+    /// semantics may change without a deprecation cycle. Application code should rely on
+    /// {@link #scan(ScanOptions)} and the typed array accessors instead.
+    /// @deprecated marked for removal once the reader-internal packages consolidate (see
+    /// {@code TODO.md}); kept here as an interim escape hatch for vortex-internal callers.
+    @Deprecated(since = "0.4.0", forRemoval = true)
     MemorySegment slice(long offset, long length);
 
     ScanIterator scan(ScanOptions options);