Implement blast-radius <providerName> verb (v0.2.0)

[Emuthmartinez]

Summary

Add the blast-radius <providerName> subcommand to the CLI. Given a Riverpod provider name, scan a Flutter/Dart repo and print every provider, widget, notifier, and test file that transitively depends on it. Static analysis only; no running app; no telemetry.

This is the hero verb for the W4 OSS launch (r/FlutterDev Show post, Code With Andrea outreach, README refresh all reference it).

Full spec

The complete implementation spec lives in the Clueless Creations harness:

workspaces/internal-portfolio/apps/riverpod-kg/artifacts/engineering/blast-radius-verb-spec.md

It covers:

• CLI surface (args, options, exit codes)
• Text / JSON / markdown output formats
• Files to touch (new: src/cli/blast-radius.ts, src/analysis/providerGraph.ts, src/analysis/dartParser.ts, src/analysis/types.ts, src/analysis/formatReport.ts; touch src/bin/riverpod-knowledge-graph.ts, README.md, package.json)
• Function signatures for buildProviderGraph, computeBlastRadius, blastRadiusCli
• Detection regexes for Riverpod 2.x + 3.x codegen
• Transitive walk algorithm (BFS, cycle-safe)
• 7 integration test cases + 5 unit test cases
• Three fixture mini-repos to add under tests/fixtures/blast-radius/
• Explicit non-goals (runtime trace, visualization, IDE plugin, network calls)

Acceptance

• pnpm test passes with new test files
• pnpm build clean
• npx . blast-radius authProvider runs against the fixture repo and matches snapshot
• README section updated under the verb table
• CHANGELOG entry: "v0.2.0 — blast-radius verb"
• Version bumped to 0.2.0 in package.json

Non-goals

• Runtime trace / devtools integration
• Graph visualization (emit JSON for other tools to consume)
• IDE plugin
• Any network calls or telemetry

Target

v0.2.0, shipped before the W4 OSS launch (2026-05-10).