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>

README.md

@@ -1,16 +1,26 @@
-# AntiDrift
+# Keel
 
-A personal focus operating system: treat each work session as an explicit
-commitment (next action, success condition, timebox), and make drift visible.
+A **human-harness** that helps Felix hold course toward his higher goals: it
+collects his real state from the tools he already uses, hands it to a swappable
+brain (`claude` / `codex` / Hermes), and acts on the reply through gated
+effectors — surfaced on a web UI and the WM status bar. The brain, the storage
+(ActivityWatch), and the data sources are reused; the harness is what we build.
 
-> **This repo is the seed of [Keel](docs/keel-architecture.md)** — a human-harness
-> that helps Felix hold course toward his higher goals. AntiDrift's focus harness
-> becomes Keel's first *mode*; the broader architecture (collectors, AW-as-memory,
-> swappable brain, web UI, gated effectors) is in `docs/keel-architecture.md`. The
-> repo/code rename is deferred until the controller-refactor decision.
+> **Architecture:** [`docs/keel-architecture.md`](docs/keel-architecture.md) is the
+> source of truth. **Agents:** read [`AGENTS.md`](AGENTS.md) first.
 
-See `docs/superpowers/specs/` for the focus-OS design; `docs/keel-architecture.md`
-for where it's headed.
+## Focus mode (AntiDrift)
+
+What runs in this repo *today* is **AntiDrift**, Keel's first mode: a personal
+focus operating system that treats each work session as an explicit commitment
+(next action, success condition, timebox) and makes drift visible. Keel
+generalizes its controller so a focus-session becomes one mode among several
+(house, body, review, capture). The milestone history below is this mode's record.
+
+> **Naming:** the directory and git repo are renamed to `keel`; the *code identity*
+> is intentionally still `antidrift` (Go module, `antidriftd` binary, `~/.antidrift/`
+> runtime, `ANTIDRIFT_*` env). The code rename lands with a state migration during
+> the controller refactor — see `docs/keel-architecture.md` §8.
 
 ## Run
 
@@ -82,6 +92,6 @@ works.
 
 M1 (evidence & audit): active-window tracking, two-tier evidence store
 (disposable per-session raw log + permanent hash-chained session summaries),
-and live SSE updates. Live drift judgment and the ambient nudge arrive in later
-milestones (see the roadmap in
-`docs/superpowers/specs/2026-05-31-go-focus-os-design.md`).
+and live SSE updates. Live drift judgment and the ambient nudge arrived in later
+milestones (M3 and M3.5 above; the original roadmap spec has since been removed —
+code and git history are the record).