Only memory comes from the server's /mcp; notes, knowledge and skills stay local

Harness spec 3.0.0 (acp.md *Memory*): memory records are the server's for the
device as for a chat; everything else in the library is the device's own.

- `library: lembas` (the default when the login's token has the `memory`
  scope, or the older `library`) adds the server's /mcp with its `memory`
  tool alone, in place of this machine's memory tool; notes_*, knowledge_*
  and skill_* are always this machine's. No prompts, resources or
  instructions are taken from it.
- The memory in the prompt is the server's: the resource lembas://memory,
  read as a session starts (McpManager.readResource) and kept for it — put in
  while nothing has been sent, so the prompt never changes under a session.
- A session the client opened (session/new, or opened from the store) sends
  its id as `_meta.lembas.scope` on every memory call and on the resource
  read (App.setScope); a session of the device's own sends none.
- An instance's `library` context (its knowledge bases) is no longer read:
  the knowledge block names this machine's bases only.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

schema/config.schema.json

@@ -996,7 +996,7 @@
       "type": "boolean"
     },
     "library": {
-      "description": "Global config only. local (default): memory, notes, skills and knowledge on this machine. lembas: the account's on the LLeMbas instance you are logged in to, through its /mcp — the same tools its chats have (needs a login with the library scope).",
+      "description": "Global config only. Where memory lives. lembas (the default when the login may reach it): the account's memory records on the LLeMbas server, through its /mcp — the same records its chats have. local: this machine's memory files. Notes, knowledge bases and skills are this machine's either way.",
       "type": "string",
       "enum": [
         "local",