docs(15-01): complete Logto Docker infrastructure plan

- Create 15-01-SUMMARY.md with execution results
- Update STATE.md with phase 15 position and decisions
- Update ROADMAP.md with plan progress
- Mark AUTH-04 requirement complete

.planning/phases/15-external-authentication/15-01-SUMMARY.md

@@ -0,0 +1,102 @@
+---
+phase: 15-external-authentication
+plan: 01
+subsystem: infra
+tags: [logto, oidc, docker-compose, postgres]
+
+# Dependency graph
+requires:
+  - phase: 14-postgresql-migration
+    provides: Postgres database and Docker Compose foundation
+provides:
+  - Logto OIDC provider running as Docker Compose service
+  - Postgres init script for separate Logto database
+  - OIDC environment variable documentation
+  - Schema without users/sessions tables (ready for external auth)
+affects: [15-02, 15-03, 16-multi-user-data-model]
+
+# Tech tracking
+tech-stack:
+  added: [logto (svhd/logto Docker image)]
+  patterns: [multi-database Postgres init via docker-entrypoint-initdb.d, OIDC env var convention]
+
+key-files:
+  created:
+    - docker-compose.yml
+    - docker-compose.dev.yml
+    - docker/init-logto-db.sql
+    - .env.example
+  modified:
+    - src/db/schema.ts
+
+key-decisions:
+  - "Logto shares Postgres instance via separate database created by init script"
+  - "OIDC_ISSUER derived from LOGTO_ENDPOINT in docker-compose, not separately configured"
+
+patterns-established:
+  - "Docker init scripts in docker/ directory mounted to docker-entrypoint-initdb.d"
+  - "OIDC environment variables: LOGTO_ENDPOINT, LOGTO_CLIENT_ID, LOGTO_CLIENT_SECRET, OIDC_AUTH_SECRET"
+
+requirements-completed: [AUTH-04]
+
+# Metrics
+duration: 3min
+completed: 2026-04-04
+---
+
+# Phase 15 Plan 01: Logto Docker Infrastructure and Schema Cleanup Summary
+
+**Logto OIDC provider added to Docker Compose with Postgres init script, users/sessions tables removed from schema**
+
+## Performance
+
+- **Duration:** 3 min
+- **Started:** 2026-04-04T18:35:52Z
+- **Completed:** 2026-04-04T18:38:52Z
+- **Tasks:** 2
+- **Files modified:** 6
+
+## Accomplishments
+- Added Logto as a Docker Compose service in both production and dev configurations with proper health-check dependency on Postgres
+- Created Postgres init script that automatically creates the logto database on first boot
+- Removed users and sessions tables from GearBox schema, generated Drizzle migration to drop them
+- Documented all required OIDC environment variables in .env.example
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Add Logto service to Docker Compose and create init script** - `625862f` (feat)
+2. **Task 2: Remove users and sessions tables from schema** - `0fe231f` (feat)
+
+## Files Created/Modified
+- `docker-compose.yml` - Production compose with Postgres, Logto, and app services
+- `docker-compose.dev.yml` - Dev compose with Postgres and Logto for local auth testing
+- `docker/init-logto-db.sql` - SQL script creating separate logto database on Postgres
+- `.env.example` - Documents all required environment variables for OIDC configuration
+- `src/db/schema.ts` - Removed users and sessions table definitions
+- `drizzle/0010_foamy_marvel_zombies.sql` - Migration to drop users and sessions tables
+
+## Decisions Made
+- Logto shares the same Postgres instance but uses a separate database (created by init script), rather than a dedicated Postgres container
+- OIDC_ISSUER is derived from LOGTO_ENDPOINT in docker-compose.yml rather than being a separate top-level env var, reducing configuration duplication
+- Dev compose uses hardcoded password for Logto DB connection (matching existing dev Postgres pattern)
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+None.
+
+## User Setup Required
+None - no external service configuration required. Logto admin console setup (creating OIDC application, obtaining client ID/secret) will be needed before plan 15-02, but is handled as part of the Logto first-boot experience at http://localhost:3002.
+
+## Next Phase Readiness
+- Logto infrastructure is ready for plan 15-02 (server-side OIDC integration)
+- Schema is cleaned of old auth tables, ready for OIDC-based authentication
+- API keys table preserved for continued programmatic access
+
+---
+*Phase: 15-external-authentication*
+*Completed: 2026-04-04*