fix(utils): include port 65535 in get_free_port() scan range

[miclaldogan]

Summary

• range(start_port, 65535) in get_free_port() excluded port 65535, the last valid TCP port
• Changed upper bound to 65536 so the full valid range 0–65535 is covered
• The existing error message already referenced 65535, making the off-by-one visible

Change

- for port in range(start_port, 65535):
+ for port in range(start_port, 65536):

Test plan

• Verify get_free_port(65535) now succeeds when port 65535 is free
• Verify existing port allocation behavior is unchanged for normal port ranges

Closes #2023

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[greptile-apps]

Greptile Summary

This PR fixes a classic off-by-one error in get_free_port() where range(start_port, 65535) silently excluded port 65535 — the last valid TCP port. The error message already referenced 65535 as the upper bound, making the inconsistency visible.

• Off-by-one fix: Upper bound changed from 65535 to 65536 so range() now covers the full valid port space through 65535.
• Error message consistency: The existing "No free port found between {start_port} and 65535" message on line 118 remains accurate since the scan now correctly reaches 65535.

Confidence Score: 5/5

Minimal, correct single-line fix with no side effects on the surrounding logic.

The change is a single range upper-bound adjustment that makes the function's behavior consistent with its own error message. All existing port-scanning logic, error handling, and Ray-reserved-port exclusion remain untouched.

No files require special attention.

Important Files Changed

Filename	Overview
nemo_curator/core/utils.py	One-line fix to include port 65535 in the scan range by changing upper bound from 65535 to 65536; no other logic changes.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A["get_free_port(start_port)"] --> B["for port in range(start_port, 65536)"]
    B --> C{Port in Ray reserved range?}
    C -- Yes --> B
    C -- No --> D["Try socket.bind(localhost, port)"]
    D -- Success --> E["Return port"]
    D -- OSError --> F{get_next_free_port and port == start_port?}
    F -- "False (strict mode)" --> G["Raise RuntimeError: Port in use"]
    F -- True --> B
    B -- "Exhausted (was: stopped at 65534, now: stops at 65535)" --> H["Raise RuntimeError: No free port found"]

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_{Reviews (6): Last reviewed commit: "Merge branch 'main' into fix/get-free-po..." | Re-trigger Greptile}

[VibhuJawa]

LGTM

[sarahyurick]

/ok to test 6ecacb8

[sarahyurick]

/ok to test 954a7eb