Context
-------
Wealthfolio's activity `notes` field is user-editable via the UI, so
using it as the dedup key would let a single note-edit in Wealthfolio
cause the next sync to create a duplicate. Stress-testing the plan
flagged this as the top structural risk.
This change
-----------
- SQLite-backed store at `/data/broker_sync.db` in production; keyed on
(provider, account, external_id) so each provider's id space is
scoped to its own account.
- `INSERT OR IGNORE` makes record() idempotent — second call with the
same key is a no-op and preserves the original wealthfolio_activity_id
plus first_seen timestamp.
- `filter_new()` is the integration point: provider fetches activities,
hands them to the store, gets back only the unseen subset to submit
to the Wealthfolio sink.
- Wealthfolio activity id returned by the API is persisted alongside
each record so the HMRC FX reconciliation job can later PATCH the
original activity rather than creating a new one.
Test plan
---------
## Automated
- poetry run pytest tests/test_dedup.py -v → 6 passed
- poetry run mypy broker_sync tests → Success: no issues found in 6 source files
- poetry run ruff check . → All checks passed!
## Manual Verification
Not applicable for this layer — full end-to-end verification happens
once a provider + sink land (Phase 1 Trading212 and the auth spike).
Context
-------
New connector suite that syncs UK brokerage activity (Trading212,
InvestEngine, Schwab email-parsed, CSV drop-folder) into Wealthfolio.
Lives outside finance/ intentionally — finance/ is untouched per the
plan at ~/.claude/plans/let-s-work-on-linking-temporal-valiant.md.
This change
-----------
- Poetry project with httpx, typer, bs4, dev tools (pytest, mypy strict,
ruff, yapf).
- Canonical Activity + Account models with the 6 UK tax wrappers
(ISA/SIPP/GIA/LISA/JISA/WORKPLACE_PENSION) and the 12 Wealthfolio
activity types from docs/activities/activity-types.md on the upstream.
- Validation invariants: BUY/SELL need qty+price, DIVIDEND/DEPOSIT/etc
need amount — raises early so providers can't silently emit broken
rows.
- to_wealthfolio_csv_row() shape matches Wealthfolio's CSV import;
primary sink path per the plan.
Test plan
---------
## Automated
- poetry run pytest -q → 7 passed in 0.03s
- poetry run mypy broker_sync tests → Success: no issues found in 4 source files
- poetry run ruff check . → All checks passed!
- poetry run yapf --diff --recursive broker_sync tests → no diff
## Manual Verification
Not applicable — pure data model, no runtime behaviour.
Closes: code-thw.1
