fix(#2012): scope phase.complete Progress-row regex to ## Progress section (#2032)

* fix(#2012): scope Progress-row regex to ## Progress section (was binding to earlier table)

The Progress-row writer used a non-global regex that matched ANY table row
starting with the phase number. When an earlier table (e.g. Requirements
coverage | Phase | Requirements | Count |) preceded ## Progress, the regex
bound to the wrong row (3-column), no-op'd, and never reached the real
Progress row. roadmap_updated stayed true (it's existsSync), masking the
failure.

- src/phase.cts: scope the tableRowPattern regex to the ## Progress section
  (indexOf + slice) so it only matches Progress-table rows.
- tests/phase.test.cjs: regression test — ROADMAP with a phase-numbered
  Requirements table before ## Progress → Progress row updated, Requirements
  row untouched.

Closes #2012

* docs(#2012): backfill changeset pr 2032

src/phase.cts

@@ -1460,7 +1460,10 @@ function cmdPhaseComplete(cwd: string, phaseNum: string, raw: boolean): void {
           `^(\\|\\s*${phaseEscaped}\\.?\\s[^|]*(?:\\|[^\\n]*))$`,
           'im',
         );
-        roadmapContent = roadmapContent.replace(tableRowPattern, (fullRow) => {
+        // Scope the Progress-row search to the ## Progress section so the regex
+        // doesn't bind to an earlier table (e.g. | Phase | Requirements | Count |)
+        // whose rows also start with the phase number. (#2012)
+        const updateProgressRow = (fullRow: string): string => {
           const cells = fullRow.split('|').slice(1, -1);
           const dateShape = /^\d{4}-\d{2}-\d{2}$/;
           if (cells.length === 5) {
@@ -1477,7 +1480,15 @@ function cmdPhaseComplete(cwd: string, phaseNum: string, raw: boolean): void {
             cells[3] = dateShape.test(existingDate4) ? cells[3] : ` ${today} `;
           }
           return '|' + cells.join('|') + '|';
-        });
+        };
+        const progressIdx = roadmapContent.indexOf('## Progress');
+        if (progressIdx >= 0) {
+          const beforeProgress = roadmapContent.slice(0, progressIdx);
+          const progressSection = roadmapContent.slice(progressIdx);
+          roadmapContent = beforeProgress + progressSection.replace(tableRowPattern, updateProgressRow);
+        } else {
+          roadmapContent = roadmapContent.replace(tableRowPattern, updateProgressRow);
+        }
 
         const planCountPattern = new RegExp(
           `(#{2,4}\\s*Phase\\s+${phaseEscaped}[\\s\\S]*?\\*\\*Plans:\\*\\*\\s*)[^\\n]+`,