compile: directory argument silently no-ops instead of auto-discovering or erroring #867

Summary

ado-aw compile <dir> silently produces 0 compiled, N skipped instead of either (a) auto-discovering the *.md files in that directory, or (b) failing loudly with a clear "expected a file, got a directory" error.

Repro

$ ado-aw compile tests/safe-outputs/
# Detects 26 lock files, reports "(up to date)" for each, then
# emits "Warning: source ... not found for ... skipping" for each,
# and exits 0 with "0 compiled, 26 skipped, 0 failed".

tests/safe-outputs/README.md (line 102–107) currently documents this exact form as the canonical recompile command:

# Recompile every fixture in this directory (idempotent):
cargo run -- compile tests/safe-outputs/

…so the README is also out of sync with actual behavior.

What works today

• ado-aw compile <file.md> — single file, works as documented.
• ado-aw compile (no args) — autodiscovers from cwd, works as documented.
• Per-file loop: for md in tests/safe-outputs/*.md; do ado-aw compile --force "$md"; done — works but is awkward.
• cd tests/safe-outputs/ && ado-aw compile — autodiscovers the 26 lock files but their source: tests/safe-outputs/... headers are relative to repo root, so each one is skipped with a "source not found" warning.

Observed in the wild

The recompile-safe-output-fixtures agentic workflow (PR #863, fixed in #864) was triggered against release v0.31.1 and silently did nothing because it used the documented compile tests/safe-outputs/ form. Full log: https://github.com/githubnext/ado-aw/actions/runs/27020309715/job/79746499042.

The agent then correctly inspected the lock files, saw version=0.31.1 matching the latest release, and emitted noop — masking the fact that the compile invocation never did any work. A subsequent integrity check would have caught the masking, but the root cause is the silent skip on a directory argument.

Proposed behaviour

When path resolves to an existing directory:

1. Walk it (non-recursively, or recursively — match the autodiscovery behaviour) for *.md files that are agentic-pipeline sources.
2. Compile each.
3. Print the same per-file summary lines that the no-args form prints.

If walking yields zero candidates, exit with a non-zero code and a clear error rather than 0 compiled, 0 skipped.

Less-good alternatives

• Reject directory args with a hard error and a hint pointing at the no-args form. Better than the current silent-skip behaviour but worse than DWIM.
• Update only the README to document the per-file loop. Doesn't fix the surprise for everyone else.

Workaround for now

for md in tests/safe-outputs/*.md; do
  ado-aw compile --force "$md"
done

This is what the recompile-safe-output-fixtures workflow now does (PR forthcoming after this issue is filed).