Flash Redirect Helpers + ResponseContext

[kainovaii]

Pull Request: Flash Redirect Helpers + ResponseContext

Summary

Adds typed redirect helpers to BaseController (redirectWithSuccess, redirectWithError, etc.) and introduces ResponseContext to eliminate req, res boilerplate in flash redirects.

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Changes

1. ResponseContext — ThreadLocal for Response

Added: livecomponents/http/ResponseContext.java

• Mirrors the existing RequestContext pattern: ThreadLocal<Response> with set(), get(), clear()
• Enables controllers to access the current response without passing it through the call chain

2. SessionMiddleware — wire ResponseContext

Modified: SessionMiddleware.java

• ResponseContext.set(res) added alongside RequestContext.set(req) in handle()
• ResponseContext.clear() added to the static clear() method to prevent memory leaks

3. BaseController — typed flash redirect helpers

Modified: BaseController.java

• redirectWithFlash() now uses RequestContext.get() / ResponseContext.get() instead of the non-existent Spark.request() / Spark.response()
• Added redirectWithSuccess(), redirectWithError(), redirectWithWarning(), redirectWithInfo()
• Cleaned up duplicate imports (spark.Request was imported twice, import static spark.Spark.* was unused)

// Before
setFlash(req, "success", "Kit créé");
res.redirect("/kits");
halt();

// After
redirectWithSuccess("Kit créé", "/kits");

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Breaking Changes

redirectWithFlash(Request req, Response res, String type, String message, String location) signature changed to redirectWithFlash(String type, String message, String location). Any existing calls passing req, res must be updated to drop those parameters.