feat: complete legacy UI and playout parity migration

tools/MBN_STOCK_WEBVIEW.DbWriteSmoke/README.md

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+# Development database write smoke
+
+This executable is deliberately separate from the read-only `DbSmoke` tool. It
+does not load database configuration or make a database call unless the exact
+write acknowledgement is present:
+
+```powershell
+dotnet run --project tools/MBN_STOCK_WEBVIEW.DbWriteSmoke/MBN_STOCK_WEBVIEW.DbWriteSmoke.csproj -- `
+  --i-understand-this-writes-development-database
+```
+
+Use `--configuration <path>` only when the normal LocalAppData configuration is
+not the intended development configuration. Credentials, SQL, generated
+identities, and database values are never printed.
+
+The plan covers every migrated database writer:
+
+- all four Oracle GraphE `INPUT_*` screens;
+- Oracle AList/PList definition creation and item replacement;
+- ThemeA KRX (Oracle) and NXT (MariaDB) creation;
+- EList expert creation (Oracle).
+
+Each scenario uses a legacy-column-safe 20-character
+`MBW<UTC-date><40-bit nonce><scenario>` name,
+proves that name is absent, performs each production-service mutation once,
+reads the row back through the production read service, deletes it in `finally`,
+and verifies absence. Numeric legacy keys cannot contain the prefix, so their
+production next-code service supplies the numeric key and the conditional insert
+still rejects a concurrent collision without overwriting an existing row. A
+bound, read-only child-row preflight also rejects keys that have legacy orphaned
+`PLAY_LIST`, `SB_ITEM`, or `RECOMMEND_LIST` rows, so cleanup cannot delete an
+older row.
+
+Both read and write retries are disabled. If a mutation outcome is unknown, the
+tool stops immediately and issues no retry, cleanup mutation, or later scenario.
+Its redacted output then reports that the uniquely prefixed row may require
+manual inspection.
+
+If a known-committed manual smoke row could not be parsed or deleted, reconcile
+only the tool-owned current-UTC-date namespace with:
+
+```powershell
+dotnet run --project tools/MBN_STOCK_WEBVIEW.DbWriteSmoke/MBN_STOCK_WEBVIEW.DbWriteSmoke.csproj -- `
+  --reconcile-known-owned-manual-residue `
+  --i-understand-this-writes-development-database
+```
+
+The recovery refuses a truncated or non-singular per-table match and never
+retries a delete.