feat(installer): do shallow clones

[ethernet8023]

What does this PR do?

The installer scripts (install.sh and install.ps1) currently do full clones of the hermes-agent repo, pulling the entire history. For a one-shot install that just needs the latest files on a given branch, this is unnecessary — it wastes bandwidth and makes the clone noticeably slower on large repos.

This PR adds --depth 1 to all four git clone invocations (SSH + HTTPS in both scripts) so the installer only fetches the tip of the branch. This is safe because:

• The installer never pushes back to the cloned repo — it's read-only.
• Post-clone steps (checkout, setup) only need the working tree, not history.
• git pull inside the install dir will still work (Git auto-expands the shallow boundary on pull).

Related Issue

Fixes #

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 🔒 Security fix
• 📝 Documentation update
• ✅ Tests (adding or improving test coverage)
• ♻️ Refactor (no behavior change)
• 🎯 New skill (bundled or hub)

Changes Made

• scripts/install.sh: Added --depth 1 to both SSH and HTTPS git clone commands
• scripts/install.ps1: Added --depth 1 to both SSH and HTTPS git clone commands

How to Test

1. Run scripts/install.sh on a Linux/macOS machine — verify it clones successfully and the installed dir has the expected files
2. Run scripts/install.ps1 on a Windows machine — verify same
3. Confirm the cloned .git directory is shallow: git -C <install-dir> rev-list --count HEAD should return 1

Checklist

Code

• I've read the Contributing Guide
• My commit messages follow Conventional Commits (fix(scope):, feat(scope):, etc.)
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this fix/feature (no unrelated commits)
• I've run pytest tests/ -q and all tests pass
• I've added tests for my changes (required for bug fixes, strongly encouraged for features)
• I've tested on my platform: NixOS (Linux)

Documentation & Housekeeping

• I've updated relevant documentation (README, docs/, docstrings) — or N/A
• I've updated cli-config.yaml.example if I added/changed config keys — or N/A
• I've updated CONTRIBUTING.md or AGENTS.md if I changed architecture or workflows — or N/A
• I've considered cross-platform impact (Windows, macOS) per the compatibility guide — or N/A
• I've updated tool descriptions/schemas if I changed tool behavior — or N/A

Screenshots / Logs

N/A — no visual changes.

Infographic

[github-actions]

🔎 Lint report: ethie/shallow-clone-installer vs origin/main

ruff

Total: 0 on HEAD, 0 on base (➖ 0)

🆕 New issues: none

✅ Fixed issues: none

Unchanged: 0 pre-existing issues carried over.

ty (type checker)

Total: 9840 on HEAD, 9840 on base (➖ 0)

🆕 New issues: none

✅ Fixed issues: none

Unchanged: 5102 pre-existing issues carried over.

Diagnostics are surfaced as warnings — this check never fails the build.