Bring every doc up to date, and give the repo a Wi-Fi template that exists

CONTEXT.md had grown by appending and contradicted itself (all four nodes vs six, a retracted CPU
figure, "no calibration", "nobody enrolled", "audio untested as a service", the Wi-Fi-off boot as
not done, a class the tracker replaced). Rewritten as one current-state document organised by
subsystem, with fresh measurements, the owner's decisions, the gotchas, the neck's arrival-day plan
and what is genuinely still open.

README: status, speakers not fitted, new-session note for Hermes, the calibration section (shipped
calibration, coverage hints, outlier dropping, --from-views), running the tests, the docs row.
HANDOFF.md gets a status banner listing where the original brief has drifted. CLAUDE.md starts at
CONTEXT.md. The echo-cancel config no longer talks about a Pi Zero, and the enclosure guide no longer
tells you to centre a servo with a tool that does not exist yet.

pi/network-config.example is a tracked, credentials-free first-boot template: the README pointed at
pi/50-cloud-init.yaml, which is gitignored and so missing from a fresh clone. The dead IdentityCache
(replaced by the tracker) is removed. Docstrings corrected: audio scope publishing, the MCP health
topics, and what the calibration tool does.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AFN8nRRCiDiMN7ChBpHJhs

ros/hermes_vision/test/test_identity_cache.py

@@ -1,40 +0,0 @@
-from hermes_vision.detect import Face
-from hermes_vision.recognize import IdentityCache, iou
-
-
-def test_iou():
-    a = Face(0, 0, 100, 100)
-    assert iou(a, a) == 1.0
-    assert iou(a, Face(200, 200, 50, 50)) == 0.0
-    assert 0.3 < iou(a, Face(50, 0, 100, 100)) < 0.4
-
-
-def test_a_tracked_face_is_identified_once_per_period():
-    calls = []
-    cache = IdentityCache(period_s=1.0)
-    ident = lambda f: (calls.append(f), 'kyle')[1]
-    assert cache.update([Face(100, 100, 80, 80)], 0.0, ident) == ['kyle']
-    for i in range(1, 8):                                  # the face drifts a little, 4 times a second
-        assert cache.update([Face(100 + i, 100, 80, 80)], i * 0.125, ident) == ['kyle']
-    assert len(calls) == 1
-    cache.update([Face(108, 100, 80, 80)], 1.1, ident)     # stale: rechecked
-    assert len(calls) == 2
-
-
-def test_a_new_face_is_identified_immediately_and_unknown_is_cached_too():
-    calls = []
-    cache = IdentityCache()
-    ident = lambda f: (calls.append(f), '' if f.x > 400 else 'kyle')[1]
-    names = cache.update([Face(100, 100, 80, 80), Face(500, 100, 80, 80)], 0.0, ident)
-    assert names == ['kyle', ''] and len(calls) == 2
-    assert cache.update([Face(101, 100, 80, 80), Face(501, 100, 80, 80)], 0.3, ident) == ['kyle', '']
-    assert len(calls) == 2                                  # the stranger is not re-embedded every frame
-
-
-def test_a_face_that_jumps_is_a_different_face():
-    calls = []
-    cache = IdentityCache()
-    ident = lambda f: (calls.append(f), 'kyle')[1]
-    cache.update([Face(100, 100, 80, 80)], 0.0, ident)
-    cache.update([Face(600, 300, 80, 80)], 0.1, ident)
-    assert len(calls) == 2

ros/hermes_vision/test/test_tracking.py

@@ -53,3 +53,11 @@ def test_a_stranger_is_unknown_not_named():
 def test_without_an_identifier_nothing_is_named():
     (t,) = FaceTracker().update([f(100)], 0.0)
     assert t.name == '' and t.id == 1
+
+
+def test_iou():
+    from hermes_vision.recognize import iou
+    a = Face(0, 0, 100, 100)
+    assert iou(a, a) == 1.0
+    assert iou(a, Face(200, 200, 50, 50)) == 0.0
+    assert 0.3 < iou(a, Face(50, 0, 100, 100)) < 0.4