Retain existing leveraged ETF shares for small accounts

[Pigbibi]

Summary

• keep an existing whole share for TQQQ/SOXL when the positive target is below one share price
• preserve existing cash-substitution behavior for other unbuyable sleeves
• add regression coverage for the sell-all-then-cannot-buy-back case

Tests

• python -m py_compile application/execution_service.py tests/test_execution_service.py
• git diff --check
• timeout 120 python -m pytest tests/test_execution_service.py -k 'existing_whole_share or unbuyable_weight_target or zero_target_sell' -q (fails in local collection: ModuleNotFoundError: No module named 'pandas')

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 46c6e09771

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[chatgpt-codex-connector]

Preserve total target notional when retaining a share

When a fully allocated small account already holds one TQQQ/SOXL share and the desired sleeve is below one share, this raises only that sleeve's target notional but leaves the other targets unchanged. For example, with $100 equity, one $80 TQQQ share, 60% TQQQ / 40% QQQM targets, and margin buying power, the effective targets become $80 + $40, so the buy loop can submit QQQM buys that take the account to 120% gross exposure instead of treating the retained extra $20 as already consuming allocation. Please offset the retained-share notional from cash/other sleeves or keep this adjustment limited to the sell floor rather than increasing total targets.

Useful? React with 👍 / 👎.