Document unicode sheet support and edge-case fixtures

Author: Arturo R Montesinos

README.md

@@ -48,8 +48,15 @@ odsview --list-sheets tests/fixtures/simple.ods
 odsview tests/fixtures/table_small.ods
 odsview --sheet Sheet2 tests/fixtures/table_small.ods
 odsview --range A1:C3 tests/fixtures/table_small.ods
+odsview --sheet Σheet-✓ tests/fixtures/unicode_sheets.ods
 ```
 
+The range-based table view has been exercised against curated fixtures
+that include mixed numeric/text/date columns, sparse sheets with
+leading/trailing empty rows and columns, long text that stretches
+column widths, and non-ASCII sheet names and cell contents (e.g.
+`Σheet-✓`, `ñandú`, `東京`).
+
 ## Curation & Guardrails
 
 This repository is instrumented for Software Curatorship. When using AI assistants

docs/adr/0004-table-view-cli-behavior.md

@@ -64,7 +64,8 @@ surface:
 - If `--sheet` is omitted:
   - Use the **first** sheet as listed by `Workbook.sheets`.
 - If `--sheet NAME` is provided:
-  - Match sheet by **exact name** (case-sensitive).
+  - Match sheet by **exact name** (case-sensitive), including
+    non-ASCII names such as `Σheet-✓`.
   - If not found:
     - Print a clear error on `stderr` (e.g. `sheet 'NAME' not found`).
     - Exit with code `1`.