Add local repo scan import

[clyons]

Purpose / Big Picture

A new VibeFocus user often already has a folder full of local git repositories, but the current setup path still expects them to create projects one at a time before the app becomes useful. This PR adds a fast, safe onboarding path from “I have a directory of repos” to “VibeFocus has my portfolio.”

The scan is intentionally lightweight: it creates or updates project records, stores local paths, infers GitHub remotes and basic metadata, and refreshes read-only git stats. It does not import commit logs during first scan, so the initial import stays quick; users can run Analytics sync later when they want heatmaps, velocity, streaks, and health history.

Summary

Adds a local git repository import path for fresh VibeFocus installs:

• scans a backend-visible directory for git repos from Settings or make import-projects
• creates or updates projects idempotently by local_path, github_url, then name
• infers GitHub URLs from origin, local path, tech stack, description, status, priority, and lightweight git stats
• keeps commit-log import out of scan so first import stays fast; Analytics sync remains the explicit path for heatmaps/velocity/history
• shows clear Settings guidance for unconfigured or missing directories, including Docker mount cases
• fixes the new-project drawer cache race and labels the Settings button distinctly from States/Categories

Fixes #1.

Notes

Local repo import works without an Anthropic API key. AI chat and analysis still require a configured Anthropic key when those features are used.

Local planning reference in the fork workspace: .agent/execplans/2026-05-11-local-repo-scan-onboarding.md.

Validation

• make fe-build
• cd backend && ./venv/bin/python -m py_compile main.py import_local_projects.py services/*.py routers/*.py
• CLI empty-db smoke with no Anthropic key:
  • first run: 2 repos created, 0 commit rows imported
  • second run: same 2 repos updated, no duplicates
• API empty-db smoke with no Anthropic key:
  • GET /api/data/scan-config reports configured temp repo root as ready
  • first POST /api/data/scan: created: 2, updated: 0, skipped: 0
  • second POST /api/data/scan: created: 0, updated: 2, skipped: 0
  • database count after both scans: 2 projects, 0 commit rows
• Error smoke:
  • missing scan root returns scan_root_missing
  • unconfigured scan root returns scan_root_required