filesystem: make edit/edit_lines the default, smart_edit a last-resort fallback ...

Agent overused smart_edit (whole-file LLM call, weak context). Rewrite the
FilesystemTool description decision tree so edit (exact text) is the default and
edit_lines (by line numbers) is the deterministic option; smart_edit is reserved
for genuinely semantic changes that cannot be expressed as exact text or line
numbers. Strengthen the old_not_unique hint to steer back to edit/edit_lines
before smart_edit. Add an "Editing policy" section to the navi_code and
developer profile prompts reinforcing the same priority.

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

Update Navi Code profile: config, prompts, docs, and env example ...

- Sync navi_code profile tools with current codebase (memory, schedule_recall, manage_recall, switch_profile, list_profiles)

- Remove image_view and MCP tools from navi_code; keep local terminal focus

- Update system prompt and persona for terminal-first coding assistant

- Update docs/navi_code.md, docs/profiles.md, docs/config.md for new tool set

- Refresh .env.navi_code.example with current config variables

- Remove stale CLI prototype directories (cli/, navi_code_cli/)

Navi Code: Phase 1 — terminal-first profile, default profile mechanism, env/persona, tests ...

- Add navi_code profile (terminal-first coding assistant)
- Add NAVI_DEFAULT_PROFILE_ID setting and POST /sessions default profile fallback
- Add persona_navi_code.txt and .env.navi_code.example
- Add docs/plan_navi_code.md phased plan
- Update tests to verify default-profile selection in no-auth mode

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