feat: implement configurable tool container home directory

- Add ToolType.home_directory column with default /home/user
- Add Alembic migration to add column, set existing rows, and rewrite
  /workspace to /home/user/{{WORKSPACE_NAME}} in legacy templates
- Add merge migration fc8f1a20cbf6 to resolve Alembic multiple heads
- Update manifest compiler to honor manifest.home_directory for HOME,
  WORKDIR, /workspace symlink, and default repo mount target
- Update legacy dockerfile/compose instance generation to use
  tool_type.home_directory
- Thread resolved home_dir through config profile and git mount expansion
- Generate entrypoint permission fixer to chown home/mounts at startup
- Update base.dockerfile with sudo/passwordless sudo for permission fixer
- Add unit tests for manifest compiler, instance service, and migrations
- Add placeholder integration test for container lifecycle
- Update openspec/tasks/home-path-expansion.md task checkboxes
- Update project maps for modified files

Quality gates: py_compile, ruff, mypy, pytest tests/unit (205 passed),
pytest tests/integration (110 passed, 35 skipped). Alembic round-trip
and container lifecycle integration tests require Docker/PostgreSQL.

openspec/tasks/.pi-map.md

@@ -4,17 +4,17 @@ dir: openspec/tasks
 index: openspec/tasks/.pi-map.index.md
 
 ## role
-Technical specification and task tracking directory for planned engineering improvements across the project's container runtime, workspace management, and developer tooling systems.
+Contains technical specification documents tracking planned features and architectural improvements for the project.
 ## files
 - config-profile-multi-repo-mounts.md | Technical specification for refactoring git mount configuration to support multiple repository mappings per mount instead of single source/target pairs | dep: git, docker compose, react/typescript, pytest, npm, fastapi
-- home-path-expansion.md | Defines a technical implementation plan for adding configurable home/workspace directory support to tool containers in an API service. | dep: SQLAlchemy/Alembic, Docker, Docker Compose, Jinja2 templating, pytest, npm/frontend tooling
+- home-path-expansion.md | Design and implementation plan for adding configurable home/workspace directory support to tool containers in an API application. | dep: SQLAlchemy/Alembic, Docker, Docker Compose, pytest, PostgreSQL, Node.js/npm
 - mount-specificity-ordering.md | Tracks completion status of a project task for implementing mount specificity ordering in Docker volume handling | dep: docker.py, pytest, tsc
 - terminal-responsiveness.md | A technical specification document outlining 7 pending tasks to improve web terminal performance through asyncio-native I/O, binary WebSocket frames, WebGL rendering, flow control, and comprehensive benchmarking. | dep: asyncio, WebSocket, xterm-addon-webgl, docker, pytest
 - tool-definition-manifest.md | A project task specification document defining a multi-PR system for implementing a Tool Definition Manifest System with backend manifest compilation, frontend workshop UI, and legacy migration support. | dep: SQLAlchemy, Alembic, Docker, Docker Compose, FastAPI/REST API, React/TypeScript frontend
 ## arch
-Markdown-based living documentation pattern using standalone specification files that each capture a discrete technical initiative with implementation plans, completion tracking, and cross-referencing between backend API changes, frontend UI work, and infrastructure migrations.
+Markdown-based task tracking system using standalone specification documents that each define discrete feature work across backend, frontend, and infrastructure concerns.
 ## tags
-mount, docker, pytest, tool, manifest, technical, specification, support
+mount, docker, pytest, tool, manifest, specification, support, docker compose
 ## symbols
 -
 ## workflows