Add claude-profile engagement mode picker with statusline and session-start integration

- claude-profile: phase 1-3 picker (profile, mode, launch) with preset support,
  dryrun, WezTerm theming, and --append-system-prompt mode body injection
- 5 mode files (chat/quick/deep/hybrid/orch) with YAML frontmatter + prose body;
  new escalates_to field drives statusline →Opus arrow for deep and hybrid
- statusline.sh reads CLAUDE_CONFIG_DIR/active-mode.env to show
  [Sonnet→Opus] deep · topic format when launched via claude-profile
- Root CLAUDE.md session-start: auto-selects project from cwd or CLAUDE_PROJECT
  in active-mode.env, skipping the interactive picker when context is clear
- Spec, tests (37 assertions, 9 test files, all passing), context docs, and
  preset example included

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -25,10 +25,16 @@ small-scripts/
 │   └── <script-name>
 ├── tests/             # Test scripts (one per main script)
 │   └── test-<script-name>.sh
+├── data/              # Read-only data files consumed by scripts
+│   └── <script-name>/ # One subdirectory per script that needs data
 └── memory/            # Tiered memory topic files
     └── log/           # Session logs
 ```
 
+### data/ directory
+
+Some scripts need static data that is too large or too structured to embed inline (e.g. `claude-profile` reads engagement mode definitions from `data/claude-profile/modes/*.md`). Put such data under `data/<script-name>/`. Treat it as read-only at runtime — user customisation belongs in the user's config directory, not in `data/`. Example files (e.g. `presets.yaml.example`) live alongside the data and are copied by the user into their config dir.
+
 ## Workflow
 
 ### Adding a new script