test: handle quoted Windows config paths

[floze-the-genius]

Summary

Keeps the existing %q path formatting and updates TestLoadServerURL to require the corresponding strconv.Quote(path) representation. Quoted paths retain the useful visibility of whitespace and control characters while making the assertion correct on Windows.

On non-Windows systems, the test now uses a valid filename containing a literal backslash. That reproduces the Windows escaping mismatch in every local and hosted run instead of relying on the runner OS to expose it.

Type of change

• Bug fix
• New feature
• Refactor / cleanup
• Docs
• Infrastructure / CI
• Breaking change

Areas touched

• apps/server (NestJS)
• apps/web (React / Vite)
• apps/agent (Go)
• packages/protocol (shared WebSocket contracts)
• infrastructure / .github/workflows
• docs

Related issues

Closes #99

How to test

1. cd apps/agent
2. go test ./internal/config/ -run TestLoadServerURL -count=1 -v
3. go test ./...

The synthetic backslash path produced the issue's exact RED failure before the assertion change. The final complete agent suite also passes on windows-latest in an isolated fork-only validation run: https://github.com/floze-the-genius/docksight/actions/runs/31455527967

Checklist

• Change is focused and stays within the existing modular monolith boundaries.
• Ran the relevant checks locally.
• Documentation is unchanged because no module boundary or protocol changed.
• No ADR is needed for this test-only portability fix.

Local verification: focused RED/GREEN regression, full go test ./..., go vet ./..., go build ./..., go mod tidy drift check, all four release-target cross-compiles, Windows test-binary cross-compile, and git diff --check.

Protocol changes

Not applicable; packages/protocol is untouched.

Screenshots

Not applicable; no UI change.

[floze-the-genius]

@rodriguecyber The focused fix for #99 is ready at one current test-only commit. The synthetic backslash path reproduced the exact failure on macOS before the strconv.Quote(path) assertion, and the final full agent suite passes locally plus on a real windows-latest runner: https://github.com/floze-the-genius/docksight/actions/runs/31455527967. The upstream Agent workflow is stopped at action_required before jobs start. Could you approve it and review when convenient?