## 1. Sequential Foundation

- [x] 1.1 Backend data model and migrations. Add config profile, ordered include, mount/file, default selection, and tool instance selected-profile storage. Remove launch-time reliance on legacy active config folder auto-mounting. Depends on: none. Parallel with: none.

## 2. Parallel Backend Core After Foundation

- [x] 2.1 Profile resolver service. Implement recursive ordered include resolution, deterministic merge rules, save-independent cycle protection, and resolved output structures for env vars, runtime hints, mounts, file trees, and override metadata. Depends on: 1.1. Parallel with: 2.2, 2.3.
- [x] 2.2 Profile CRUD, validation, compatibility, and default APIs. Implement user-owned CRUD, access checks, path/content validation, ordered include save validation, compatibility-filtered listing, and default profile selection APIs. Depends on: 1.1. Parallel with: 2.1, 2.3.
- [x] 2.3 Instance API profile selection plumbing. Update instance create/start request and persistence paths to accept one compatible config profile ID or null, reject incompatible selections, and preserve `None`. Depends on: 1.1. Parallel with: 2.1, 2.2.

## 3. Sequential Backend Integration

- [x] 3.1 Resolved profile preview API. Return final env vars, runtime hints, mount targets, mount modes, relative file paths, and practical override indicators. Depends on: 2.1, 2.2. Parallel with: none.
- [x] 3.2 Launch and restart profile application. Apply resolved profile output during start by writing env vars, staging files, adding Docker bind mounts, applying supported runtime hints, skipping profile output for `None`, and using the stored profile on restart instead of current defaults. Depends on: 2.1, 2.3. Parallel with: none.

## 4. Parallel Frontend After Backend Contracts

- [x] 4.1 Frontend config profile API client and types. Add client methods/types for profile CRUD, includes, defaults, compatible listing, preview, and instance profile selection payloads. Depends on: 2.2, 2.3, 3.1. Parallel with: none.
- [x] 4.2 Settings profile management UI. Add settings surfaces for browsing profiles, editing env vars/runtime hints/mounts/text files/include order/defaults, and preserving draft edits on validation errors. Depends on: 4.1. Parallel with: 4.3.
- [x] 4.3 Launch profile selection UI. Update session start UI to load compatible profiles for the selected project/tool, preselect the resolved default, offer `None`, and submit selected profile ID or null. Depends on: 4.1. Parallel with: 4.2.

## 5. Parallel Test Suites

- [x] 5.1 Backend profile API and resolver tests. Cover CRUD, ownership, path validation, compatibility filtering, default precedence, include ordering, save-time cycle rejection, resolution-time cycle protection, and deterministic override behavior. Depends on: 2.1, 2.2, 3.1. Parallel with: 5.2, 5.3.
- [x] 5.2 Backend instance launch tests. Cover selected profile start/restart behavior, incompatible profile rejection, `None` selection, env var writing, file staging, Docker mount application, runtime hints, and legacy active config folders not auto-mounting. Depends on: 3.2. Parallel with: 5.1, 5.3.
- [x] 5.3 Frontend profile UI tests. Cover profile settings editing, validation error handling, compatible profile loading, default preselection, `None` selection, and submit payloads. Depends on: 4.2, 4.3. Parallel with: 5.1, 5.2.

## 6. Sequential Quality Gates

- [x] 6.1 Run backend quality gates for touched API/model/services code and fix failures. Depends on: 5.1, 5.2. Parallel with: none.
- [x] 6.2 Run frontend quality gates for touched settings/session UI code and fix failures. Depends on: 5.3. Parallel with: none.
- [x] 6.3 Run final OpenSpec status and implementation checklist review. Depends on: 6.1, 6.2. Parallel with: none.
