Accept negative-score search cursors as option values

[Widthdom]

Summary

• accept syntactically valid negative-score search cursors as separated --cursor values
• keep recognized short options such as -q from being consumed as cursor data
• extend the bounded shared test-session timeout from 60 to 75 minutes so the slower Windows lane can finish within the existing 90-minute job bound
• document both contracts in English and Japanese and add bilingual changelog fragments
• merge the latest origin/main through b72ebf595

Root cause

Issue #4664: the shared string-option reader rejected every separated value beginning with -. Recipe search scores are commonly negative, so replay commands generated from next_cursor were interpreted as a missing --cursor value followed by an unsupported option.

Issue #4705: the Windows net8.0 lane reached the repository-wide 3,600,000 ms test-session timeout with 9,347 passed, 0 failed, and 3 skipped tests. Restore and build took about 90 seconds, leaving sufficient room under the 90-minute job timeout for a bounded 75-minute test session.

Impact

Generated recipe/audit pagination commands can replay negative-score cursors unchanged and return the next result page. Other dash-prefixed tokens retain their prior option-parsing behavior. The Windows CI suite remains bounded but is no longer aborted exactly at 60 minutes before completing.

Validation

• dotnet restore CodeIndex.sln --locked-mode
• final Debug solution build: succeeded with 0 warnings and 0 errors
• final Release solution build: succeeded with 0 warnings and 0 errors
• Issue Accept negative-score search cursors as option values #4664 plus CiWorkflowTests: 12 passed on net8.0
• cursor regression suite: 38 passed on net8.0 during adversarial review
• Issue Accept negative-score search cursors as option values #4664 tests: 2 passed on net8.0 and 2 passed on net9.0 before the final no-conflict main merge
• QueryCommandRunnerTests: 1,539 passed and 1 documented platform-specific test skipped on net8.0 before the final no-conflict main merge
• make lint
• dotnet run --project tools/CodeIndex.Changelog --no-restore -- check (98 fragments)
• Codex adversarial review round 1 found one stale 45-minute documentation reference; it was fixed in both language sections
• Codex adversarial review round 2: No blocking/actionable issues found.

Documentation and changelog

• README.md
• TESTING_GUIDE.md
• changelog.d/unreleased/4664.fixed.md
• changelog.d/unreleased/4705.internal.md

Fixes #4664
Fixes #4705