Fix search aliases and ranking guidance

[Widthdom]

Summary

• Add search --max-results as a --limit alias and improve dash-prefixed query recovery hints.
• Improve search --path glob expansion guidance when shell-expanded paths become extra positional arguments.
• Strengthen punctuation-heavy exact-substring rerun guidance across CLI JSON/text and MCP recovery hints.
• Boost normal multiword literal searches so chunks containing the exact phrase rank ahead of token-only matches.

Validation

• dotnet build CodeIndex.sln -c Debug -p:UseSharedCompilation=false
• dotnet test tests/CodeIndex.Tests/CodeIndex.Tests.csproj -c Debug --filter "FullyQualifiedName~Issue3521|FullyQualifiedName~Issue3445|FullyQualifiedName~Issue3389|FullyQualifiedName~PunctuationHeavy" -p:UseSharedCompilation=false
• dotnet run --project tools/CodeIndex.Changelog -- check
• dotnet ./src/CodeIndex/bin/Debug/net8.0/cdidx.dll status --check --json

Issues

Fixes #3521
Fixes #3445
Fixes #3386
Fixes #3389

Follow-up Issues

None.

Agent/Workflow Notes

• No existing work-started comments were found before starting these issues.
• Added changelog fragments under changelog.d/unreleased/.
• Adversarial review: No blocking/actionable issues found.
• Did not modify AGENTS.md, CLAUDE.md, or AGENT_GUIDE.md.