docs: the estimate and plans say accounts are minted on first write, not on every start #7

• didbot crates/didbot-agentd/src/context.rs:254-260 provisions on Began as well as Acted, so every SessionStart (including after /clear) and every SubagentStart creates a permanent account. didbot docs/agentd.md:164 agrees with the code.
• tools/estimate.py:75-77 prints "a name is minted when a context first publishes something, and most never do". The README sends people to it before they install.
• plan/harnesses.md:96-97 and plan/first-run.md:49-51 say the same.
• README.md:50 says "nothing leaves the machine"; with didbot-agentd running, every session creates a server account.
• hook.py:7, README.md:53-56 and plan/collection.md say the hook sends "identifiers, never values ... file paths", but hook.py:279 sends cwd.

Failure: a prospective installer is told most sessions create nothing, and gets one permanent account per session and per subagent.

Suggested fix: correct the estimate, the plans and the README. Whether the daemon should mint only on Acted is a didbot decision for the owner.

Filed by Claude (agent) from a static read of main at a590e52.