docs: make Keel the repo front door + add agent context

- README: lead with Keel (the human-harness), frame AntiDrift as the focus
  mode, keep the milestone history. Fix the "rename deferred" wording (the
  dir/repo is already keel; only the code identity stays antidrift) and drop
  the dangling 2026-05-31 spec reference (that spec was intentionally removed).
- keel-architecture.md: update the rename status in the header and §8 — the
  directory is keel; the Go module / antidriftd binary / ANTIDRIFT_* env /
  ~/.antidrift -> ~/.keel migration land with the controller refactor.
- add AGENTS.md (agent orientation) + CLAUDE.md symlink so claude / codex /
  Hermes auto-load Keel context when launched in this repo.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/keel-architecture.md

@@ -18,12 +18,14 @@ status: authoritative
 > **Name & home.** *Keel* is the system: a human-harness that helps Felix hold
 > course toward his higher goals. The name answers AntiDrift's metaphor — *drift*
 > is what a vessel does with nothing to hold it; the *keel* resists drift and
-> keeps you on an even keel (steady mind). **This repo (`antidrift`) is Keel's
-> seed**: AntiDrift's focus harness becomes Keel's first *mode*. The code/repo
-> rename is **deferred** until the controller-refactor decision (§8); for now
-> only this design doc lives here as the authoritative home. Moved from
-> `~/dev/higher/` on 2026-06-04 — that directory was the scaffold where the
-> decision to extend AntiDrift was made, and now retires.
+> keeps you on an even keel (steady mind). **This repo is now `keel`** — AntiDrift's
+> focus harness becomes Keel's first *mode*. The directory and git repo are
+> renamed; the **code identity is intentionally still `antidrift`** (Go module
+> `antidrift`, binary `antidriftd`, runtime `~/.antidrift/`, `ANTIDRIFT_*` env).
+> That *code* rename is **deferred** until the controller refactor (§8) because
+> `~/.antidrift/` owns the live ledger/state and needs a migration, not a `mv`.
+> Moved from `~/dev/higher/` on 2026-06-04 — that directory was the scaffold where
+> the decision to extend AntiDrift was made, and now retires.
 
 ---
 
@@ -245,8 +247,10 @@ behavioral story) or left out initially.
   `~/owc/stream.md` vs `~/wrk/pkb/stream.md` vs dead inboxes) and rewiring `blurt`
   to append there.
 - **Controller refactor shape** — how invasive the AntiDrift generalization is; do
-  we branch the daemon or grow it in place. **This is also the trigger for the
-  repo/code rename to `keel`.**
+  we branch the daemon or grow it in place. **This is also when the *code* rename
+  lands** — Go module / `antidriftd` binary / `ANTIDRIFT_*` env and
+  `~/.antidrift/` → `~/.keel/` with a state migration. (The directory is already
+  `keel`; only the code identity still says `antidrift`.)
 - **Cross-device AW** — sync work-laptop AW or not (see §7).
 - **Secret hygiene** — an increasingly autonomous operator runs as the full Unix
   user; plaintext keys exist on disk; the privacy boundary in ③ must be real.