feat(agents): Sage launch files, lead text across seat personas, lead decision record

- agents/sage/ launch files committed after Dewey's review (R1 revise, R2
  approve). The launcher test now covers sage with its zai/glm-5.3 high pin.
  The README states the lead role and its limits, and the seat reads but
  never writes the old DYOR records under ~/.mosaic.
- N6 (Dewey authored, Sage reviewed against pins): seat personas and the
  Rocko launcher name Sage as project lead and Darkwing as a collaborating
  engineering seat, per Jason's 2026-09-26 ruling.
- docs/plans/2026-09-26_lead-decisions.md: the push, no merge into next and
  its conditions, the board restart, queue-as-data rulings, Gate F waiting
  on a T3 source, and what stays with Jason.

Launcher tests 6/6 and 1/1, eight suites green. Not pushed.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

agents/rocko/launch.sh

@@ -46,7 +46,7 @@ for file in "${CONTEXT_FILES[@]}"; do
 done
 STATE="$REPO/.pi/state/rocko"
 echo "rocko: native host TUI | $VERSION | model sonnet"
-echo "rocko: workspace $REPO | team lead Darkwing"
+echo "rocko: workspace $REPO | project lead Sage"
 if "$CHECK"; then
     echo 'rocko: configuration checks passed (no TUI, authentication request or model call)'
     exit 0