feat: add --quiet flag for summary-only terminal output

[stark256-spec]

Summary

Resolves #8

• Adds -q, --quiet flag to debtlens scan
• In quiet mode, only the header and summary counts are printed — individual findings (file paths, rule names, evidence, suggestions) are suppressed
• Exit code behaviour is fully preserved — --fail-on still works correctly
• Only affects terminal format; JSON/markdown/SARIF are unaffected

Changes

• src/cli/index.ts — add -q, --quiet option to the scan command
• src/reporters/index.ts — thread quiet through renderReport
• src/reporters/terminalReporter.ts — return early after summary lines when quiet: true
• tests/reporters/terminalReporter.test.ts — new test file covering quiet and normal output (4 tests)

Test plan

• All 69 existing tests pass
• Quiet mode omits individual findings
• Quiet mode still prints summary line
• Normal mode output unchanged

[ColumbusLabs]

Thanks for the PR!

CI is currently failing because the new DebtIssue test fixture is missing the required tags field:

tests/reporters/terminalReporter.test.ts(23,7): Property 'tags' is missing ... but required in type 'DebtIssue'.

Could you add tags: [] to the test issue fixture and push an update? After that, CI should be able to continue through the rest of the workflow.

[ColumbusLabs]

Review

Looked through the diff after CI passed on Node 20 and 22.

Looks good

• --quiet is wired CLI → renderReport → renderTerminal with an early return after the summary block.
• Exit code / --fail-on path is untouched (only reporting changes).
• Tests cover default output, quiet suppression, and empty-scan quiet behavior.
• tags: [] on the fixture matches DebtIssue.

Nit (non-blocking)

• Help text says “summary line” but quiet mode still prints the header and scan metadata lines; consider “summary only” if you want the flag description to match output.

Approved from maintainer pass — thanks for the contribution.