fix(agents): add observability to work-item image download

[zbigniewsobiecki]

Summary

• Root cause diagnosed: fetchWorkItemStep silently discarded image downloads when downloadAttachment returned null — no log entry was emitted, making failures completely invisible in run logs (only container stdout was written, which is never captured in cascadeLog)
• Add INFO/WARN log calls around the parallel image download block so every outcome — start, per-image failure, and final summary — appears in the run log
• Fix pre-existing URL credential leak: the exception-path WARN already present was logging the full URL including Trello query-param credentials (key=, token=); both WARNs now strip query params with .split('?')[0]
• Fix stray lowercase log level: builderFactory.ts had a single logWriter('warn', ...) inconsistent with the codebase-wide 'WARN' convention

Changes

File	Change
src/agents/definitions/contextSteps.ts	INFO before Promise.all (count), WARN on null return (sanitized URL), INFO after (attempted/downloaded/skipped); fix URL sanitization in existing exception WARN
src/agents/shared/builderFactory.ts	'warn' → 'WARN' to match convention
tests/unit/agents/definitions/contextSteps.test.ts	Replace 2 tests + add 1 new test covering: null-return WARN with URL sanitization, exception WARN with URL sanitization, INFO log counts

Test plan

• All 5963 unit tests pass locally
• Typecheck clean
• Pre-push hooks (lint + typecheck + changed-file unit tests) pass
• On next run with an image-bearing work item, run logs will show:
  • [INFO] fetchWorkItemStep: downloading work item images { count: N }
  • [WARN] fetchWorkItemStep: image download returned null { url: <no query params> } (on failure)
  • [INFO] fetchWorkItemStep: image download complete { attempted: N, downloaded: M, skipped: K }

🤖 Generated with Claude Code

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Codecov Report

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