chore: bring dev's token list onto main, making main the single trunk

[enot3615]

Replaces #47, which could not merge: main's protection is strict, so the head
must be up to date with the base, and dev is 3 commits behind. This is the same
content on a branch cut from main, so it satisfies that without pushing to a
shared branch.

What it brings

dev's only unique content — the chain-verified internal token list (AIFINP-78,
merged to dev as #24):

12 files changed, 1665 insertions(+), 0 deletions(-)

A new node/internal-tokenlist package. Zero deletions, so it cannot alter
anything already on main.

Why main is the trunk

The decisive fact is not a preference:

origin/main: occurrences of the old royalty code = 0   ← #42 fix present
origin/dev:  occurrences of the old royalty code = 1   ← fix ABSENT

_splitter_treasury(pm[ is still in python/aifinpay/unified_agent.py on dev.
Anything built on dev inherits taking the merchant's royalty — disqualifying
for the branch about to carry v1.3 settlement execution.

dev has never produced a release	no tags unique to it; one feature since 2026-08-15
CI does not distinguish them	ci.yml triggers on bare push: / pull_request:, no branch filter
No publish automation	releases are manual, so neither branch is mechanically special
Protection favours main	4 required checks vs 3
So does practice	7 of 11 open PRs already target main

Two long-lived branches with no mechanical difference and no promotion rule was
the actual defect. They diverged twice, and a money-path fix sat on one side of
the split.

After this lands

1. Retarget feat(sdk): generate SPLITTER_ROUTES from the canonical registry, and fail closed on the policy window #40 to main — verified it applies cleanly.
2. Build the v1.3 execution PR on main. That is the answer to the question
   that was blocking it.
3. Delete dev, or reset it to main and agree a promotion rule first.
   Recreating it without one recreates this PR in a month.