chore: release v5.0.0

[hogan-yuan]

Release v5.0.0.

Bumps the workspace version 4.5.0 → 5.0.0 and closes out the [Unreleased]
CHANGELOG section as [5.0.0] - 2026-09-14. Major bump: this release carries
breaking API changes across every language binding.

Base includes everything on main through #581 (the comparison_symbols
switch, verified live against production) and #591 (history_executions paging).

Breaking changes (7)

• Removed GridContext.submit_strategy_questionnaire (POST /v1/record/questionnaire) and SubmitStrategyQuestionnaireOptions across all bindings.
• WarrantStatus gains an Unknown variant (first variant) — shifts the ordinal of existing variants in C/C++/Java/Node.js/Python.
• WarrantInfo.expiry_date is now optional (empty server dates no longer fail the whole warrant_list).
• FundamentalContext.industry_rank takes typed IndustryRankIndicator / IndustryRankSortType (+ Market) instead of three free-form strings.
• FundamentalContext.us_financial_statement takes a typed FinancialStatementKind instead of a free-form kind string.
• Write methods on AlertContext (add/update/delete) and SharelistContext (delete/add_securities/remove_securities/sort_securities) now return () / void / Promise<void>.
• FundamentalContext.ratings (GET /v1/quote/ratings) is temporarily unavailable (server-side 暂不开放) — commented out across all bindings; StockRatings types retained.

Added (7), Changed (14), and Fixed (12) are detailed in CHANGELOG.md.

Changelog housekeeping

Consolidated the interleaved duplicate [Unreleased] section headers
(Breaking changes ×2, Fixed ×3) into one section each, ordered
Breaking → Added → Changed → Fixed, and removed 4 duplicate Fixed entries
(the C/C++ null-pointer, C++ AssetContext, and C lb_statement_item_t items
each appeared twice). No entry content was dropped other than the duplicates.
Added one new entry for #581 under Changed.

To publish after merge

1. Fast-forward the release branch to the merge commit: git push origin <merge-sha>:release (triggers the Release workflow → crates.io / PyPI / npm / Maven Central / S3).