Replace AddWithValue in symbol lookups

[Widthdom]

Summary

• Replaced the remaining GetSymbolsAtLine AddWithValue calls with SqliteCommandPolicy.Add typed parameter binding.
• Added AnalyzeFileLine coverage for line lookup with kind and lang filters.

Validation

• dotnet test tests/CodeIndex.Tests/CodeIndex.Tests.csproj --filter "FullyQualifiedName~AnalyzeFileLine_WithKindAndLanguageFilters_ReturnsSymbolAtLine_Issue4057"
• dotnet ./src/CodeIndex/bin/Debug/net8.0/cdidx.dll audit dotnet-risk-patterns --path src/ --json (sqlite-addwithvalue count: 0)
• dotnet run --project tools/CodeIndex.Changelog -- check
• dotnet format CodeIndex.sln --verify-no-changes --include src/CodeIndex/Database/DbSymbolReader.cs tests/CodeIndex.Tests/DbReaderTests.cs --no-restore
• dotnet test tests/CodeIndex.Tests/CodeIndex.Tests.csproj --filter "FullyQualifiedName~Extract_JavaScriptLargeExportedObjectLiteralProperties_CompletesWithinPracticalBudget" -p:UseSharedCompilation=false
• dotnet ./src/CodeIndex/bin/Debug/net8.0/cdidx.dll status --check --json

Full-suite note: dotnet test tests/CodeIndex.Tests/CodeIndex.Tests.csproj --settings tests/CodeIndex.Tests/CodeIndex.Tests.runsettings --blame-crash --blame-hang --blame-hang-timeout 5m -p:UseSharedCompilation=false was attempted under concurrent local indexer load and hit an unrelated practical-budget timeout in Extract_JavaScriptLargeExportedObjectLiteralProperties_CompletesWithinPracticalBudget; the same test passed/skipped as expected when rerun directly.

Documentation / Changelog

• Added changelog fragment: changelog.d/unreleased/4057.fixed.md.
• No guide or user documentation changes were needed for this internal binding-policy fix.

Follow-up Candidates

None.

Fixes #4057