fix(xo-server-netbox): use numeric comparison to find the most specific prefix

[matlantin]

Fixes #10240.

Root cause

In packages/xo-server-netbox/src/index.js, the "find the smallest (most specific) prefix" logic destructures bits from prefix.split('/'), which is a string, then compares it with >/=== against highestBits:

let smallestPrefix
let highestBits = 0
nbPrefixes.forEach(({ prefix }) => {
  const [range, bits] = prefix.split('/')
  ...
  if (... && bits > highestBits) {
    smallestPrefix = prefix
    highestBits = bits
  }
})

The first comparison (bits > 0) works correctly because JS coerces the string to a number when compared against a number. But once highestBits itself becomes a string (assigned from bits), every subsequent comparison is lexicographic, not numeric: "8" > "24" evaluates to true ('8' > '2' character-by-character), even though 8 < 24 numerically.

Effect: a prefix with a single-digit mask (typically a /8 container/supernet prefix) wins over any two-digit, more specific prefix (/10-/79) that also matches the IP, regardless of the order nbPrefixes is iterated in. The same bug affects the later idempotency check (bits === highestBits), which never matches once bits and highestBits are of different types.

Real-world repro: a NetBox instance with the common container-prefix hierarchy 10.0.0.0/8 (container) → 10.10.0.0/16 (container) → 10.10.10.0/24 (active) — syncing a VM with IP 10.10.10.7 creates 10.10.10.7/8 in NetBox instead of the expected 10.10.10.7/24. Subnets without a competing single-digit-mask container prefix (e.g. a bare 192.168.1.0/24 with no /8 registered) are unaffected, which is why this went unnoticed for a while.

Fix

Force numeric comparison in both places, matching the change validated on a production instance (fixed real IPs that were previously synced as /8):

- if (parsedRange.kind() === ipKind && parsedIp.match(parsedRange, bits) && bits > highestBits) {
+ if (parsedRange.kind() === ipKind && parsedIp.match(parsedRange, bits) && Number(bits) > highestBits) {
    smallestPrefix = prefix
-   highestBits = bits
+   highestBits = Number(bits)
  }

- return nbCompactIp === xoCompactIp && bits === highestBits
+ return nbCompactIp === xoCompactIp && Number(bits) === highestBits

Testing

• Verified against a live NetBox instance: before the fix, VMs on a 10.x.x.x subnet with a 10.0.0.0/8 container prefix registered were synced with a /8 mask; after the fix (deployed to the running xo-server, followed by xo-cli netbox.synchronize), the same VMs are synced with their correct, more specific /24 mask, and re-running the sync is idempotent (no repeated create/delete).
• node --check passes on the modified file. This package has no existing unit tests to run.

[matlantin]

Rebased onto current `master` (the branch had fallen behind after a release cleared `CHANGELOG.unreleased.md`'s package list) and re-added `xo-server-netbox patch` there. Also applied the `bits`-as-number suggestion in a follow-up commit — replied on that thread.

@pdonias your directly-pushed changelog wording (issue link) is preserved, it matched what I'd already written when resolving the rebase conflict on that file.

All 3 review comments should be addressed now.