add PR support

[jtydhr88]

bounty task https://www.notion.so/drip-art/Add-Comfy-CLI-feature-to-check-out-a-single-PR-launch-comfy-and-run-a-set-of-tests-1f36d73d36508074b1c3fc56d13f4346?source=copy_link

add --pr arg, support format:

• "username:branch-name"
• PR number such as "#123"
• PR link, such as "https://github.com/comfyanonymous/ComfyUI/pull/123"

full command:
comfy --workspace=G:\comfy-cli-test install --pr "https://github.com/comfyanonymous/ComfyUI/pull/8597"
then
comfy --workspace=G:\comfy-cli-test launch

[codecov]

Codecov Report

Attention: Patch coverage is 80.12422% with 32 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
comfy_cli/command/install.py	73.07%	28 Missing ⚠️
comfy_cli/cmdline.py	33.33%	2 Missing ⚠️
comfy_cli/git_utils.py	95.12%	2 Missing ⚠️

Flag	Coverage Δ
unittests	48.14% <80.12%> (+2.56%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
comfy_cli/command/github/pr_info.py	100.00% <100.00%> (ø)
comfy_cli/cmdline.py	47.67% <33.33%> (-0.17%)	⬇️
comfy_cli/git_utils.py	67.64% <95.12%> (+41.72%)	⬆️
comfy_cli/command/install.py	47.81% <73.07%> (+14.96%)	⬆️

... and 5 files with indirect coverage changes

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[christian-byrne]

Strengths

• Excellent test coverage (376 lines of tests)
• Clean separation of concerns
• Good error handling with rich formatting
• Handles both fork and same-repo PRs correctly

Possible Improvements

Critical:

1. Parameter validation bug (cmdline.py:348): The condition version != "nightly" or commit will be true if version is None, preventing valid use cases. Should be version not in {None, "nightly"} or commit.

Important:

2. Timestamp formatting (install.py:381): The reset_time is displayed as a Unix timestamp instead of human-readable format.
3. Deleted fork handling (install.py:579): Missing null check will cause KeyError if PR is from a deleted fork.
4. Branch name sanitization (git_utils.py:87): Git will reject branch names with special characters.

Suggestions:

5. Docstring placement (install.py:184): Move docstring before code execution.
6. Remote naming (git_utils.py:70): Consider using pr-{number}-{user} to avoid conflicts when checking out multiple PRs from same author.

[jtydhr88]

@christian-byrne fixed your feedback except Timestamp formatting, this is an existing code used in checkout version, I just move it into a function could be shared in my new logic

[jtydhr88]

btw, regarding to failing test, I checked it and likely failed on download something on the MAC machine, not caused by my changes I believe