docs: fix overclaiming OriginKind comment and trim restated test comments

Enum comment claimed package-id lookup that no persisted field supports; reworded
to the real distinction. Trimmed CLAUDE.md-duplicated test comments and the header.

src/core/tracking/origin_ledger.h

@@ -15,14 +15,12 @@ namespace reasampler::tracking {
 // lifted from a legacy path-only manifest, or one whose creator did not know.
 // PERSISTED AS INTEGERS: never renumber an existing value, only append.
 enum class OriginKind {
-    Unknown   = 0,
-    Capture   = 1,
-    Ingest    = 2,
-    Recapture = 3,  // regenerated in place from its recorded source recipe
-    Resample  = 4,  // baked from an instrument's own processing chain
-    // Kept distinct from Ingest — both bring in a foreign file, but only this one
-    // can answer "which package did this bank come from" later.
-    PackageImport = 5,
+    Unknown       = 0,
+    Capture       = 1,
+    Ingest        = 2,
+    Recapture     = 3,  // regenerated in place from its recorded source recipe
+    Resample      = 4,  // baked from an instrument's own processing chain
+    PackageImport = 5,  // package-sourced vs Ingest's user-picked; unrecoverable once merged
 };
 
 // One system-created file's birth record. `relativePath` is the key and is ALWAYS