iter or.1.6-fix: correct git rebase syntax + README cross-ref wording

skills/implement/SKILL.md

@@ -105,7 +105,7 @@ structure). Read it. The end-report is the only thing that costs the
 Boss-context tokens; per-task chatter has stayed inside the
 orchestrator-agent.
 
-### Step 3 — Boss merge step (on DONE / PARTIAL with partial DONE-tasks)
+### Step 3 — Boss merge step (on DONE; also for PARTIAL when some commits landed cleanly)
 
 1. Open the per-iter journal file on the branch:
    `git show iter/<iter_id>:docs/journals/<YYYY-MM-DD>-iter-<iter_id>.md`
@@ -115,8 +115,11 @@ orchestrator-agent.
    preserved verbatim.
 3. Append one line to `docs/journals/INDEX.md`:
    `- YYYY-MM-DD — iter <iter_id>: <one-line title> → <YYYY-MM-DD>-iter-<iter_id>.md`
-4. Rebase the iter branch onto main:
-   `git rebase iter/<iter_id> onto main` (or fast-forward if linear).
+4. Fast-forward main to the iter branch:
+   `git switch main && git merge --ff-only iter/<iter_id>`. Since the
+   iter branch was created from `origin/main` (Phase 0 of the
+   orchestrator-agent) and no commits have landed on main since, the
+   fast-forward is always linear.
 5. Optionally delete the branch: `git branch -D iter/<iter_id>`.
 6. If trigger is done-state and the user is away, write a
    `docs/WhatsNew.md` entry + `notify.sh` per CLAUDE.md's
@@ -190,5 +193,6 @@ merges and updates `docs/journals/INDEX.md`. No further hand-off —
     mini-mode
 - **Output target:** Boss reads the end-report and the per-iter
   journal; `audit` runs at milestone close.
-- **Documented exception:** in `skills/README.md`, this is the named
-  exception to "agents do not call other agents".
+- **Documented exception.** `ailang-implement-orchestrator` is the
+  named exception to "agents do not call other agents". The same
+  exception is described in `skills/README.md` (Conventions section).