Phase 3: coaching preferences + weekly check-in engine

Add coaching preferences (auto-derived from the profile, user-overridable) and
a periodic check-in engine that quotes the person's own words and asks whether
their direction still feels valid — mirror, not compass.

- Preferences are deterministic: a documented triad mapping (gut → direct/
  higher-friction, heart → warm/drift-sensitive, head → reflective/question-led)
  produces defaults for the six fields (coaching_frequency, coaching_style,
  misalignment_threshold, friction_tolerance, prefer_questions_over_directives,
  time_of_day_preference). PUT overrides; regenerate re-derives.
- CheckinCoach (app/services/coaching.py): Anthropic-backed; writes a check-in
  that quotes the person's goals back and asks if the direction still holds.
- Endpoints (app/routers/coaching.py): GET/PUT/regenerate preferences;
  GET/POST checkins; respond (records still_valid); admin POST /run is the
  weekly batch (due = cadence elapsed + locked profile), intended for a cron.
- Models + migration 005: coaching_preferences (per user) and coaching_checkin.
- Frontend: coaching.html (preferences form + check-in feed); linked from
  profile.html.

Tests: 68 passing (added deterministic-preference unit tests and coaching
endpoint/batch tests; run in-container). README updated for Phase 3.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

alembic/versions/005_add_coaching.py

@@ -0,0 +1,106 @@
+"""add coaching_preferences and coaching_checkin (Phase 3)
+
+Revision ID: 005
+Revises: 004
+Create Date: 2026-06-16
+
+Phase 3: coaching preferences (auto-generated from the profile, user-overridable)
+and periodic coaching check-ins that quote the person's own words and ask
+whether their direction still feels valid.
+"""
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+from alembic import op
+
+revision: str = "005"
+down_revision: Union[str, None] = "004"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "coaching_preferences",
+        sa.Column("id", sa.String(), primary_key=True),
+        sa.Column(
+            "user_id",
+            sa.String(),
+            sa.ForeignKey("users.id"),
+            nullable=False,
+            unique=True,
+        ),
+        sa.Column(
+            "profile_id",
+            sa.String(),
+            sa.ForeignKey("discovery_profile.id"),
+            nullable=True,
+        ),
+        sa.Column("coaching_frequency", sa.String(), nullable=False),
+        sa.Column("coaching_style", sa.String(), nullable=False),
+        sa.Column("misalignment_threshold", sa.String(), nullable=False),
+        sa.Column("friction_tolerance", sa.String(), nullable=False),
+        sa.Column(
+            "prefer_questions_over_directives",
+            sa.Boolean(),
+            nullable=False,
+            server_default=sa.text("1"),
+        ),
+        sa.Column("time_of_day_preference", sa.String(), nullable=False),
+        sa.Column(
+            "auto_generated",
+            sa.Boolean(),
+            nullable=False,
+            server_default=sa.text("1"),
+        ),
+        sa.Column("created_at", sa.DateTime(), nullable=False),
+        sa.Column("updated_at", sa.DateTime(), nullable=False),
+    )
+    op.create_index(
+        "ix_coaching_preferences_user_id",
+        "coaching_preferences",
+        ["user_id"],
+    )
+
+    op.create_table(
+        "coaching_checkin",
+        sa.Column("id", sa.String(), primary_key=True),
+        sa.Column(
+            "user_id",
+            sa.String(),
+            sa.ForeignKey("users.id"),
+            nullable=False,
+        ),
+        sa.Column(
+            "profile_id",
+            sa.String(),
+            sa.ForeignKey("discovery_profile.id"),
+            nullable=False,
+        ),
+        sa.Column("body", sa.Text(), nullable=False),
+        sa.Column("created_at", sa.DateTime(), nullable=False),
+        sa.Column("still_valid", sa.Boolean(), nullable=True),
+        sa.Column("response_note", sa.Text(), nullable=True),
+        sa.Column("acknowledged_at", sa.DateTime(), nullable=True),
+    )
+    op.create_index(
+        "ix_coaching_checkin_user_id", "coaching_checkin", ["user_id"]
+    )
+    op.create_index(
+        "ix_coaching_checkin_created_at", "coaching_checkin", ["created_at"]
+    )
+
+
+def downgrade() -> None:
+    op.drop_index(
+        "ix_coaching_checkin_created_at", table_name="coaching_checkin"
+    )
+    op.drop_index(
+        "ix_coaching_checkin_user_id", table_name="coaching_checkin"
+    )
+    op.drop_table("coaching_checkin")
+
+    op.drop_index(
+        "ix_coaching_preferences_user_id", table_name="coaching_preferences"
+    )
+    op.drop_table("coaching_preferences")