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>

tests/purpose.test.ts

@@ -32,7 +32,7 @@ test("every tool that can ask takes a purpose; bash says it in description; tool
   for (const name of ["edit", "write", "read", "web_fetch", "skill_manage", "task"]) expect(spec(name).properties.purpose?.description).toContain("what this call is for")
   expect(spec("bash").properties.purpose).toBeUndefined()
   expect(spec("bash").properties.description?.description).toContain("what this command is for")
-  for (const name of ["ask_user", "todo", "plan_submit", "bash_output", "bash_list", "notes_search", "note_view", "note_manage"]) expect(spec(name).properties.purpose).toBeUndefined()
+  for (const name of ["ask_user", "plan_write", "plan_update", "plan_submit", "bash_output", "bash_list", "notes_search", "note_view", "note_manage"]) expect(spec(name).properties.purpose).toBeUndefined()
 })
 
 test("split: taken out of the arguments; a server's own `purpose` stays its own", () => {