feat(discovery): add watchlist mode for targeted repo sweeps

[SDS-Mike]

Summary

• Adds a watchlist field to DiscoveryConfig — a list of "owner/repo" strings for repos you want to sweep regularly
• Adds a new contribai watchlist CLI command that iterates the watchlist, running run_targeted() on each repo
• Supports --dry-run for analysis-only mode
• Gracefully handles per-repo errors without aborting the full sweep
• Aggregates findings and PR counts across all repos

Motivation

ContribAI's existing target command works great for single repos, and hunt mode discovers repos via GitHub search. But there's a gap: running ContribAI against your own repos on a schedule.

With watchlist, you can:

discovery:
  watchlist:
    - "myorg/backend-api"
    - "myorg/frontend-app"
    - "myorg/infra-tools"

Then schedule contribai watchlist via cron for continuous automated code review across your portfolio — security scans, code quality, docs — without relying on discovery.

Test plan

• contribai watchlist with empty watchlist shows helpful config instructions
• contribai watchlist --dry-run iterates repos and reports findings without submitting PRs
• Invalid entries (missing /) are skipped with a warning
• Per-repo errors don't abort the sweep
• Final summary shows aggregated findings and PR counts

🤖 Generated with Claude Code

[tang-vu]

Thanks for the contribution @SDS-Mike! The Watchlist mode is a great bridge between single target and full hunt discovery — exactly the kind of feature power users need.

I reviewed the code and the approach is solid. There are a few things to fix before we can merge:

🔴 Blocking

1. Merge conflict in config.rs — The DiscoveryConfig struct has changed on main since you branched (we added stars_range normalization). Please rebase on main:

   git fetch origin main
   git rebase origin/main
   # resolve conflicts in crates/contribai-rs/src/core/config.rs

2. CI failing — cargo fmt — There's a formatting issue around the final println! macro (line ~133 in your diff). Please run:

   cargo fmt --all

🟡 Minor

3. Blank line in error handler (line 127 in diff) — There's a stray blank line inside the Err(e) arm. Please remove it for consistency with the rest of the codebase.

✅ Looks Good

• Config field with #[serde(default)] — correct, backward compatible
• splitn(2, '/') parsing with skip on invalid — clean
• Per-repo error handling (continue on failure) — correct approach
• Summary stats at the end — nice UX touch
• config.example.yaml documentation — helpful

Once you fix the rebase + fmt, this should be good to go! 🚀

[tang-vu]

Thanks for the contribution @SDS-Mike! The Watchlist mode is a great bridge between single target and full hunt discovery — exactly the kind of feature power users need.

I reviewed the code and the approach is solid. There are a few things to fix before we can merge:

🔴 Blocking

1. Merge conflict in config.rs — The DiscoveryConfig struct has changed on main since you branched (we added stars_range normalization). Please rebase on main:

   git fetch origin main
   git rebase origin/main
   # resolve conflicts in crates/contribai-rs/src/core/config.rs

2. CI failing — cargo fmt — There's a formatting issue around the final println! macro (line ~133 in your diff). Please run:

   cargo fmt --all

🟡 Minor

3. Blank line in error handler (line 127 in diff) — There's a stray blank line inside the Err(e) arm. Please remove it for consistency with the rest of the codebase.

✅ Looks Good

• Config field with #[serde(default)] — correct, backward compatible
• splitn(2, '/') parsing with skip on invalid — clean
• Per-repo error handling (continue on failure) — correct approach
• Summary stats at the end — nice UX touch
• config.example.yaml documentation — helpful

Once you fix the rebase + fmt, this should be good to go! 🚀

[tang-vu]

Merged! I resolved the merge conflicts and ran cargo fmt on your behalf. Thanks for the great contribution @SDS-Mike! 🚀