Harness spec 1.1.0: one plan, prototypes and the library shared; the CLI implements it

The spec: plan_write and plan_update (new, shared, offered in every mode) and
plan_submit (now shared) keep one structured plan — findings, objectives,
phases of tasks — in place of the todo list, which lives on as a former name
of plan_write. The shared system text is one text for both projects, with
variables for what differs; the mode texts, a prototypes block and a library
block are shared. acp.md: the client hands the device what only it knows
(context, library, prototypes), the plan travels as a structure (plan_state),
library calls carry the chat's scope, and a client may rewind a session.
loop.json says its numbers as numbers. Four conformance areas: plan,
prototype, library_scope, toolcall_index.

The CLI: the plan is kept per session in the store and drawn above the prompt
and on the approval card; the prompt is assembled from the spec's texts with
their variables filled; the link reads the instance's instructions,
personalization, knowledge scope and prototype offer, sends the plan as a
structure and answers rewind; library calls to the instance carry the session
as scope; a prototype written in the terminal is saved as a file and named in
the transcript; a tool-call fragment without an index continues the last call;
the default theme is Moria; dead exports and Hermes leftovers removed.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/session/store.ts

@@ -115,6 +115,20 @@ export class Store {
     this.db.query("UPDATE messages SET kind = ? WHERE session_id = ? AND id BETWEEN ? AND ? AND kind = ?").run(kind, sessionId, fromId, toId, other)
   }
 
+  /** The row of the user message that started turn `turnId` (kept with the message, engine.ts),
+   *  or undefined for a turn this session does not have. */
+  turnRow(sessionId: string, turnId: string): number | undefined {
+    // The LIKE is a prefilter; the message itself says.
+    const rows = this.db.query("SELECT id, json FROM messages WHERE session_id = ? AND role = 'user' AND kind = 'message' AND json LIKE ? ORDER BY id").all(sessionId, `%${JSON.stringify(turnId)}%`) as { id: number; json: string }[]
+    return rows.find((r) => (JSON.parse(r.json) as Message).role === "user" && (JSON.parse(r.json) as { turnId?: string }).turnId === turnId)?.id
+  }
+
+  /** How many turns start at row `fromId` or after it: the visible user messages that carry a turn id. */
+  turnsFrom(sessionId: string, fromId: number): number {
+    const rows = this.db.query("SELECT json FROM messages WHERE session_id = ? AND role = 'user' AND kind = 'message' AND id >= ?").all(sessionId, fromId) as { json: string }[]
+    return rows.filter((r) => typeof (JSON.parse(r.json) as { turnId?: string }).turnId === "string").length
+  }
+
   /** Record a compaction: what the model sees from here on starts with this summary. */
   compaction(sessionId: string, summary: string) {
     this.db