feat(board): give the plan a paste= line the operator can actually use

--plan shipped with dir= and command= as separate fields. That is right for a
driver, which moves the pane itself and then types the command, and unusable
for a person: the first operator to read a block could not act on it at all.

Joining an absolute path from one field with a command from another is not a
saved line of output. It is the step where a session gets started in the wrong
repository - the same failure the absolute dir= exists to prevent, moved from
the machine to the human.

paste= is the two already joined, cd <dir> && <command>, one thing to select.
Both forms stay: the two consumers want the same fact shaped differently, and
neither shape serves both.

Emitted only alongside command=, never once per block. A `paste=cd X && ` with
nothing after it would run the cd and then a bare newline, which fails
SILENTLY - the operator ends up in the right directory with no session started
and no error to notice.

board-selftest: 86 -> 89 checks.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011eKRzhD1RqY2MxvDEkrJAM

README.md

@@ -8,7 +8,7 @@
 
 *AI-generated: all code produced by Claude Code through dialog-driven development.*
 
-![Version](https://img.shields.io/badge/version-0.16.0-blue)
+![Version](https://img.shields.io/badge/version-0.17.0-blue)
 ![Platform](https://img.shields.io/badge/platform-Claude_Code_Plugin-purple)
 ![Hooks](https://img.shields.io/badge/hooks-1-green)
 ![Skills](https://img.shields.io/badge/skills-3-orange)
@@ -111,6 +111,8 @@ It makes **zero model calls**, which is the point rather than a detail. Under su
 
 It prints `key=value` blocks rather than prose because it has **two consumers**: the operator pasting a command, and a separate repo driving a terminal from it. Prose would make the rendered format an API that no test here could hold stable for a consumer living in another repo. Each block carries `dir=` as an absolute path — a new terminal pane inherits its anchor's working directory, so a plan that omitted it would look right and point at the wrong repo. A repo whose route line is missing or unparseable gets `command_missing=` with the reason, never an empty `command=`: a driver reading `^command=` would type a blank line into a live pane.
 
+The two consumers want the same information shaped differently, so each block carries both. `dir=` and `command=` stay separate for a driver, which moves the pane itself and then types the command. **`paste=` is the operator's line** — the two already joined into one `cd … && claude …` to select and paste. Asking a person to assemble a directory from one field and a command from another is not a saved line of output; it is the step where a session gets started in the wrong repository. `paste=` is emitted only where `command=` is, since `paste=cd X && ` with nothing after it would run the `cd` and then a bare newline, leaving you in the right directory with no session and no error.
+
 Driving a terminal from this plan deliberately lives **outside this repo**. That work is a version-pinned, undocumented composition on top of a preview API whose documented path is already broken upstream, and its blast radius reaches into other repos' running sessions. The dependency runs one way — the driver consumes the plan, the plan never knows a terminal exists — so if the terminal API breaks, the plan still prints and the operator still pastes.
 
 ## Security Model
@@ -147,7 +149,7 @@ Note that raising the inbox's priority (Rule 7) deliberately does **not** widen
 ## Development
 
     bash scripts/coord-selftest.sh    # 183 checks against a throwaway mailbox
-    bash scripts/board-selftest.sh    # 86 checks against a throwaway repo tree
+    bash scripts/board-selftest.sh    # 89 checks against a throwaway repo tree
     bash scripts/route-selftest.sh    # 73 checks, incl. the route->board round trip
     npm test                          # all three selftests via node --test