docs: scope two promises to what they cover

The startup guide's "nothing you wrote is removed" now says it's about
tidying copies, since a launch still replaces an unrecorded block that
differs from its source. rig down's help now says a community harness
only has its pane stopped, so its own processes may keep running.

docs/reference/agent-startup-guide.md

@@ -423,7 +423,7 @@ Each startup file and action specifies when it applies:
 - a launch replaces it, as launches always did, and names it (`guidance_block_refreshed_unrecorded`);
 - an exact resume or a handover leaves it, and names it as possibly stale (`guidance_block_may_be_stale`).
 
-**A file keeps one copy of each distinct block text, and nothing you wrote is removed.**
+**A file keeps one copy of each distinct block text, and tidying the copies never removes a text you wrote.**
 - **Touched markers:** a marker an editor or formatter rewrapped, with spaces or line breaks inside the comment, still reads as its block, and the next write puts it back in OpenRig's form.
 - **Collected copies:** a copy that repeats an earlier one exactly is removed. Beside a copy you edited, OpenRig's own unedited copies are removed too, and every different edited copy stays (`guidance_block_copies_removed`).
 - **A marker that lost its pair:** OpenRig can't tell where that block starts or ends, so it adds no copy beside it and names it (`guidance_block_markers_damaged`). Put back the missing marker or remove the partial block, and OpenRig's next write treats that block like any other. `rig package install` leaves such a file as it is, names it in its result (`notes`), and installs the rest. A marker without its pair beside a complete block is named too (`guidance_block_marker_unpaired`), and the block is written.

packages/cli/src/commands/down.ts

@@ -143,7 +143,8 @@ export function downCommand(depsOverride?: DownDeps): Command {
   const cmd = new Command("down").description("Tear down a rig")
     .addHelpText("after", `
 rig down stops every agent OpenRig started in the rig: their sessions end, and any work in progress stops
-with them. A session OpenRig didn't start (adopted, bound or discovered) is left running, and rig down names it.
+with them. For a community harness only its pane stops: its own processes may keep running, and rig down
+names it. A session OpenRig didn't start (adopted, bound or discovered) is left running, and rig down names it.
 Before running it, check who is working (rig ps --nodes --rig <rig>) and that the person asked for it;
 don't stop a team you didn't start unless asked. OpenRig snapshots the rig first (best-effort), and
 rig up <rig> --existing brings it back, resuming each seat's conversation where its harness allows. With