Deploy static bundle contents

[SoundBlaster]

Summary

• What changed? Updates FTP deploy to mirror the contents of dist/specgraph-public/ into SFTP_REMOTE_ROOT instead of uploading the wrapper directory.
• Link related issue/task (if any): Follow-up to first successful FTP publish creating /www/specgraph.tech/specgraph-public/.

Motivation

• Why is this change needed? The public contract expects https://specgraph.tech/artifact_manifest.json, /specs/, and /runs/, but the current mirror command publishes under /specgraph-public/.
• What problem, gap, or user need does it address? Makes the deployed layout match the documented SpecSpace HTTP-backed provider contract.

Goals

• What should this PR achieve? Publish bundle root contents directly into the configured site root.
• What is intentionally out of scope? Removing the already-uploaded legacy /www/specgraph.tech/specgraph-public/ directory from the FTP server.

Changes

• Adds lcd dist/specgraph-public before each lftp mirror upload path.
• Changes mirror source from dist/specgraph-public to . for FTPS, SFTP key, and SFTP password upload modes.
• Documents that deployment must not create a nested specgraph-public directory.
• Adds a regression test for the mirror source path.

Validation

• Tests added/updated for changed behavior
• Local checks passed

Commands run:

python3 -m pytest -q tests/test_publish_static_artifacts_workflow.py tests/test_static_artifact_deploy_plan.py tests/test_static_artifact_bundle.py
git diff --check
make test

Results:

• 23 passed in 0.16s
• 720 passed in 353.43s (0:05:53)

Risks / Notes

• Backward compatibility impact: Future deploys publish artifact_manifest.json, specs/, and runs/ at the site root instead of nested under specgraph-public/.
• Migration/config changes required: The old remote /www/specgraph.tech/specgraph-public/ directory may need manual cleanup after this deploy succeeds.
• Known limitations: This does not validate write/delete behavior until merged and deployed from main.

Checklist

• PR title clearly describes the change
• Scope is focused and minimal
• Documentation updated (or N/A)
• No secrets or sensitive data added