docs.json: duplicate navigation entry for odis-use-case-phone-number-privacy

[GigaHierz]

Follow-up from #2237.

legacy/protocol/identity/odis-use-case-phone-number-privacy is listed twice in docs.json navigation — once at group level and once inside a nested sub-group.

Nav currently has 265 raw page entries but only 264 unique.

python3 -c "
import json, collections
d = json.load(open('docs.json'))
pages = []
def walk(n):
    if isinstance(n, str): pages.append(n)
    elif isinstance(n, list): [walk(x) for x in n]
    elif isinstance(n, dict):
        for k in ('tabs','groups','pages'):
            if k in n: walk(n[k])
for t in d['navigation']['tabs']: walk(t)
print([p for p,c in collections.Counter(pages).items() if c>1])
"
# ['legacy/protocol/identity/odis-use-case-phone-number-privacy']

llms.txt deduplicates it, so there's no user-visible symptom today — this is a latent inconsistency rather than a live bug. One-line fix: delete whichever of the two entries is in the wrong place.