chore(config): T-1258 — tooling/ becomes an importable package

The skeleton the reach CLI hangs off. Nothing moves yet: this adds the
package, the bounded core/, and explicit setuptools discovery.

core/console.py is the single output path, and the split it enforces is the
whole design — stdout carries the command's actual output so `reach ... | jq`
keeps working, stderr carries the event stream as JSONL. Rendering happens at
the sink: a terminal gets human text, anything else gets raw JSONL, so a live
view and a job log are one artefact in two presentations. Emitting is
optional — the gates emit nothing — and verdict() prints once, last, carrying
its remedy as a structured field.

core/config.py resolves the repo root from __file__ against a project.yaml
sentinel, with an SR_REPO_ROOT override. No subprocess and no git call: this
is on the gate path, and cwd is not a reliable signal anyway since a hook runs
from the root and an agent call may not. Both paths are validated, because a
silent fallback is how you end up editing one checkout and checking another.

Discovery is configured explicitly rather than left to flat-layout
auto-discovery, which would have had to choose between erroring on the
ambiguity and quietly shipping client/ or docs/. Verified: top_level.txt
contains exactly "tooling".

Verified beyond the happy path — the sentinel rejects SR_REPO_ROOT=/tmp and
names both remedies; debug events are suppressed at the default threshold
while the verdict is not; stdout stays clean with stderr redirected away; and
the three unconditional push-gate checks still pass now that tooling/ is a
package, which was the real regression risk.

Two findings recorded on the tickets. make setup-venv is stale — it calls
.venv/bin/pip, but the venv was created by uv and has no pip, so the recorded
procedure and the actual state have already diverged (T-1261 owns the fix).
And settled-reach-tooling had never actually been installed: site-packages
held the dependencies but no dist-info, which follows from there being no
__init__.py to expose. This is the first commit where `import tooling` means
anything.

.venv/ was only ignored via .git/info/exclude, which is machine-local, so a
fresh clone or a new worktree did not ignore it at all.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

pyproject.toml

@@ -13,6 +13,18 @@ dependencies = [
     "Pillow==12.2.0",
 ]
 
+[tool.setuptools.packages.find]
+# Explicit, not flat-layout auto-discovery. The repo root holds client/, server/,
+# docs/, wiki/, db/ and tests/ alongside tooling/, and auto-discovery either
+# errors on the ambiguity or quietly ships something unintended (T-1258).
+#
+# Nothing needs excluding yet: the hyphenated directories (planet-gen,
+# economy-db, garment-fit, pql-migrate) are invisible to package discovery
+# because a hyphen is not a valid Python identifier, and tooling/econ-sim is a
+# Rust crate with no __init__.py. That changes in T-1250, which renames them —
+# at which point they become real packages and this include starts matching them.
+include = ["tooling*"]
+
 [project.optional-dependencies]
 dev = [
     # ruff 0.15.9 — checked clean against NVD + OSV, no CVEs on record (2026-04-05)